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1. 14 4 2 SENSORS RELATED TO AQUACULTURE ccccssssssscecececsensnsececececseseececececsenenseaeeeeeesenenssaeeeeees 14 4 3 SENSOR NETWORKS 55 A EE 16 4 3 1 Mobile ad hoc sensor networks 17 4 322 WEDS ts Miter ioctl ico Coe tae hae la oS om Coe 18 4 4 UTILIZATION AND DISTRIBUTION OF SENSOR 0 0 19 5 GRID etatis io eo ao eo Se ora sa ee o se Ou ab dose se vn Sa do aeo cage de 21 5 1 MOBILE GRID T 22 6 COMMUNICATION TECHNOLOGIES eere 0 23 6 1 old pH TERI PREMIERE EET ERE 23 6 2 50 teo sette feste entstand SE ottimi rec TM 24 6 3 I RTL IEEE ER 25 6 4 SATELLITE COMMUNICATION cerise totei ieia e i iea iE iero ai ER Ess 25 6 5 EEEE A AEEA 26 6 6 EAA AEA AEEA 26 6 7 BEUBTOOTEH AEREE AES 27 6 8 A E A EEE E 27 6 9 SUMMARY AE EERE E EAE o e A E EETA 28 7 FRAMEWORK AND MODELLING CONCEPTS 29 IMIS RE o
2. Figure 8 36 The sequence diagram for interaction between SCS and its sensors As shown the SensorControlAgent actor retrieves sensor data by querying its SensorEdge actor for sensor data The interval at which this happens is determined by the timer parameters for this type of sensor The SensorEdge actor retrieves the current sensor reading and sends it back to the SensorControlAgent actor Alternatively the sensor data can be streamed directly to the control or data agent If the data is simply of interest for storage the data is sent to the SensorDataAgent for storage until a request for a sensor report 15 received initiated through the signal RetrieveSensorData The required data is then sent and if storage capacity 15 limited the current data is erased This is similar to proactive sensor handling described in section 4 3 The simple sequence diagram for this is shown in Figure 8 37 sd Proactive sensor polling sca SensorControlAgent sda SensorDataAgent SensorData SensorDataF ormat Figure 8 37 sequence diagram for proactive sensor polling If the sensor data is of a type that has threshold parameters concerning a range of normal operations SensorControlAgent actor will compare the collected data to these values In the occurrence of a deviation the SCSControlAgent is notified and appropriate action is taken This is similar to the reactive senso
3. 1 2 PosAlertForSCS SMS Server Figure 8 50 A high level communication diagram for position alerts with ECS The CSAgent could have been notified that one of its SCS nodes may be drifting especially if personnel are present at the time but this has not been implemented for the demonstrator When the SCSSession of the SCS node which is no longer available is asked to retrieve sensor data by the sensor manager it simply replies with a PCSDown signal The SCSManager then moves on to the next SCSSession The PCSRestored signal is generated from the AdminEdge actor of the MSAgent It is propagated through the system via the CS node to the SCS node reinstating the normal mode of operations The signal is finally received by the SCSRouter actor who distributes it to both the SCSControlAgent and WindowsAPIEdge This sets the status of the SCSControlAgent back to normal and the WindowsAPIEdge disconnects the GPRS modem connection The prerequisite for these actions is that the SCS node has regained PCS and been assigned the same IP address as before the link went down Otherwise the SCSSession actor will not be able to deliver the PCSRestored signal as the SCS node will be unavailable IP address unknown It should be noted that the system itself could be enabled to detect when the PCS is back online If the SCSSession actor periodically sent a connection check type signal to the SCSRouter then this signal will
4. ConnectionUpdateToMS E ConnectionUpdateRep K SET NOW time MSConnectionUpdateTimer SET NOW time connectionCheckTimer 1 Figure 8 24 The sequence diagram for a new SCS registering with CS The main difference is that the SCSSession actor reports to CSAgent s CSSession actor that a new SCS node has been installed The SCSRouter receives a list of the other SCS nodes represented by their SCSRouters under the same CS node In addition the SCSRouter actor sends a ConnectionUpdateToMS signal to its CSAgent actors CSSession actor This is due to the functionality of the ActorFrame ActorRouter The routing table of the SCSAgent must contain the MSAgent address in order for messages to be sent to the MSAgent when the PCS goes down When the PCS is unavailable the default gateway otherwise used is unavailable Therefore the SCSAgent must regularly receive messages from CSSession This interval is specified by MSConnectionUpdateTimer timer A ConnectionCheckTimer timer is also set this timer specifies the intervals in which the SCSRouter checks the PCS link status to the SCSSession A high level communication diagram displaying messages sent between the top level distributed actors is shown in Figure 8 25 66 5 SCG A Distributed Sensor Management Network in ActorFrame comm A new SCS registers with CS
5. GPSSensorData position STOP connectionTimer CSPCSFailed mySCS 1 SPCSFailed mySCS l 1 1 CSPCSFailed mySCS PCS failure detected by SCS Figure 8 43 The sequence diagram for a failed PCS between CS and SCS The SCSRouter actor is the recipient of GetSensorUpdate signal generated by its corresponding SCSSession actor Since there is only one SCSSession per SCS it 1s simpler to handle link failures due to the one to one relationship of inter communicating actors If the connectionTimer expires before the GPSSensorData signal is received the link between the CS and SCS is assumed to be down The SCSSession report a link failure to the CSControlAgent who in turn via CSRouter alerts its CSSession The CSSession can then generate the alarms necessary to the correct personnel 8 4 3 2 Failed MCS between CS and MS In the event of a MCS failure between the CS and MS events are much similar to those of a failure between a SCS and its CS The difference is that the recipient of the messages is still the same meaning that the messages are still sent to CSSession The sequence diagram for this scenario is shown in Figure 8 44 82 5 SCG A Distributed Sensor Management Network in ActorFrame sd MCS fa
6. 29 M 29 SCG A Distributed Sensor Management Network in ActorFrame SCALE machines we Ooh tees iere ise eut 30 7 2 ERICSSON S SERVICE CREATION ARCHITECTURES 30 31 TA o AVMOIOPBTNIO s eua EA a Ee 31 36 cosine Eh UU Let Lee tsa 37 7 3 RAMSES tec oet retis E 37 DESIGN OF THE SEA CAGE GATEWAY 65 2 0 00 39 8 1 DESIGN GOALS AND CONSIDERATIONS 39 8 1 1 basic set of functional requirements esee eene 42 8 1 2 Non functional 44 8 2 OVERVIEW OF THE SYSTEM ELEMENTS ies 45 0 21 TRheNGSSnode us eee eee entree 46 9 22 ANE CS NOGE n ss eor tle 47 923 Jhe UMS node de Pete 49 51 8 3 GENERIC DESIG
7. while rs next commlink rs getInt commlinkid String commname rs getString commlinkname System out println SCS comm is commlink catch Exception e System out println Problem e toString finally Gene NE fry stmt close catch Exception e System out println e toString Seme null con null try con close catch Exception e System out println e toString 152 SCG A Distributed Sensor Management Network in ActorFrame con null return commlink public void updateSCSPosition String scsname String newpos throws Exception Connection con null Statement stmt null int affected 0 ResultSet rs null int 0 sering url aidbbe my ced Class forName com mysql jdbc Driver newInstance con DriverManager getConnection url user komtek stmt con createStatement rs gtmt executeQuery select scsid from scs where scsname scsname nimm while rs next 4 id 5 affected stmt executeUpdate UPDATE SENSOR SET sensorvalue newpos where scsid ww idr and sensortypeid 1 Tr System out println The SCS GPS has been updated eise System out println The SCS GPS has not been updated catch Exception
8. SCSPCSFailed myCS i CSList TO myCS CSList dateSCSCapabilities AddSensorToDB p myCSM SCSGPSSensorData ensorData TO myCSM ConnectionUpdateToMS ConnectionUpdateRep gt idle idle idle I I NewSCS PosAlertForSCS SsetSensorUpdater PCSRestored AdWSCUTGDBO i PosAlertForSCS GetSensorUpdate e myCSM myCSM myCS 168 SCG A Distributed Sensor Management Network in ActorFrame DBEdge e gt AddMSToDB idle idle AddCSToDB gt id gt PosAlertForSCS idle SMSEdge SCSPCS Failed gt PCSRestored SSensorStatusRestored le 169 SCG A Distributed Sensor Management Network in ActorFrame Appendix H List of signals In Table H 1 the signals and their parameters used in the SCG system demonstrator are listed The code for manual alteration can be found in section 9 5 2 Table H 1 List of signals in the SCG system Signal Parameters Requires manual alteration AddCSToDB csname String msname String AddMSToDB msname String AddSCStoDB scsname String csname String AddSensorToDB sensorname Str
9. System out println Problem e toString finally steme l mull d stmt close catch Exception System out tostring nuli try con close catch Exception e System out priantin e tostring con null public void updateCSPosition String csname String newpos throws Exception Connection con null Statement stmt null int affected 0 ResultSet rs mut iot d 0 string url Class forName com mysql jdbc Driver newInstance con DriverManager getConnection url user komtek stmt con createStatement rs stmt executeQuery select csid from cs where csname csname nmm while rs next 4 153 SCG A Distributed Sensor Management Network in ActorFrame id ros getint affected stmt executeUpdate UPDATE SENSOR SET sensorvalue newpos where csid id and sensortypeid 1 lt aay 4 System out println The CS GPS has been updated else System out println The CS GPS has not been updated catch Exception System out println Problem e toString finally 4 seme I mull try stmt close catch Exception System printin e tostrming 0 stmt nuli
10. ine public int checkSCSStatus String scsname throws Exception Connection con Statement stmt null ResultSet rs null int status 0 Exy d 151 SCG A Distributed Sensor Management Network in ActorFrame string url Class forName com mysql jdbc Driver newInstance con DriverManager getConnection url user komtek stmt con createStatement rs stmt executeQuery SELECT statusid from scs where scsname scsname while rs next status 5519 System out println SCS status is commlink catch Exception e System out println Problem e toString finally semt Wa null try stmt close catch Exception System out println e toString seme nuli if con mull f try d con close catch Exception e tostring null return status public int checkSCSCommLink String scsname throws Exception Connection con null Statement stmt null ResultSet null int commlink 0 try string uri A Class forName com mysql jdbc Driver newInstance con DriverManager getConnection url user komtek stmt con createStatement rs stmt executeQuery SELECT commlinkid from scs where scsname scsname
11. cone con close catch Exception e System out printin tosString con null eal 154 SCG A Distributed Sensor Management Network in ActorFrame Appendix E The web interface code The code of the scgstatus jsp web interface is presented here This JSP file interacts with the database specified in Appendix C This file is also part of Appendix I scgstatus jsp lt html gt lt head gt lt META HTTP EQUIV refresh content 10 URL http 129 241 219 178 8080 scgstatus jsp gt 0 page import import import java sql gt lt title gt Fish farm overview lt title gt lt head gt lt body bgcolor 6699FF gt hl Current status lt java util Date date out printin date gt lt h1 gt lt Connection dbconn ResultSet results ResultSet rs ResultSet scsresults ResultSet csresult ResultSet sensorresults Statement mssql Statement cssql Statement scssql Statement sensorsql int msid 0 0 ine O try Class forName com mysql jdbc Driver try util Date boolean doneheading false dbconn Connection DriverManager getConnection jdbc mysql localhost scgdb tiser mssql dbconn createStatement dbconn createStatement Scssql dbconn createStatement sensorsql dbconn
12. 1 1 1 4 loop 1 sensorList size GetSensorUpdate 1 gt GetSensorUpdate 1 1 1 y 1 1 1 1 1 SensorData sensorData 1 1 K 1 i i 1 1 1 1 SensorData sensorData 1 1 1 SensorData sensorData 1 1 1 1 UpdateFinished 1 1 1 1 1 1 1 1 1 1 1 1 1 I 1 1 1 I Figure 8 35 The sequence diagram for a SCS retrieving its sensors data Again the pattern for retrieving the sensor data is similar to that of the CSAgent and MSAgent and the descriptions for those procedures apply here as well An issue to be considered here is the format of the sensor data retrieved from the sensors One option is to transport it in pre defined sensor specific objects These objects can preserve the data in its original format allowing for the data to be handled by other entities Such a scenario could be that of grid computing sending sensor data to the CSAgent for processing and analysis Another option is to simply report the data as a String In this way all sensor data could be comprised into a String or defined in a XML document and reduce the number of signals and interactions necessary for sending sensor data This is simpler less bandwidth is required but some of the data density may be reduced Whether the data should be sent in a sensor specific signal or through a generic sensor signal can also be d
13. 2 RegisterSCS 2 2 SCSRegistered 2 3 SCSSetupParameters SCSAgent 1 RoleRequestMsg 1 1 RoleConfMsg To all SCSAgents registered CSAgent 2 4 NewSCS 225 MSAgent 2 5 AddSCSToDB 2 1 SC x 43 SCSList SCSAgent SList Database Figure 8 25 A high level communication diagram for a new SCS registering with CS Again this is a very similar pattern as the one connecting a CS to a MS The main difference is as previously mentioned the update of the SCS capability to the CSAgent and the MSAgent The ConnectionUpdateToMS signal from the SCSAgent to the MSAgent is not shown in this communication diagram as it would degrade the readability of the figure 8 4 1 3 Initiating the connection between a new sensor and its SCS To achieve a high level of self configuration and automation new sensors should be automatically discovered and integrated into the system The sequence diagram for this is shown in Figure 8 26 67 SCG A Distributed Sensor Management Network in ActorFrame sd A new sensor is connected to a SCS sda SensorDetectionAgent sm SensorManager Scss SCSSession css CSSession RoleRequestMsg sensortype SensorAgent scsca SCSControlAgent dbe DBEdge lt lt create gt gt 1 2 sensortype Sens
14. SCSAgent ActorFrame ActorFrame 5 MSAgent ECS antenna Eee i FCS antenna Web server Internet ECS FCS ECS FCS antenna gateway SMS server Figure 8 5 The SCG system elements nodes and deployed actors As mentioned and displayed each node will be represented in the SCG system with a dedicated actor In this thesis MCS and PCS are WLAN LAN and ECS is GPRS A FCS is not available but design considerations do take it into account 45 SCG A Distributed Sensor Management Network in ActorFrame 8 2 1 The SCS node The SCS node represents the hardware on location mounted to each sea cage This node is directly connected to the sensors and provides interaction with the rest of the system through its GPRS and WLAN capabilities It s surrounding environment and interfaces are shown in Figure 8 6 Mobile terminal Figure 8 6 The SCS environment As shown the following elements are present in the environment for which the SCS node must provide interaction for They are described in Table 8 3 Table 8 3 SCS node environment descriptions Environment Description element Sensors Each SCS node must provide sensor interaction and information retrieval MS node In the case of a communications failure the SCS node must communicate with the MS node directly CS
15. catch Exception e System out printinle tosString con mull public void addSensor String csname String scsname String sensorname throws Exception Connection con null Statement stmt null int affected 0 ResultSet rs null int sensortype 0 int parent 0 try String url Mjidbewmyeql fscgdb Class forName com mysql jdbc Driver newInstance con DriverManager getConnection url user komtek stmt con createStatement rs stmt executeQuery select sensortypeid from sensortype where sensorname sensorname while rs next sensortype rs getInt sensortypeid System out println The sensor to be added has id sensortype if csname null rs stmt executeQuery SELECT from cs where csname csname nimm while rs next parent crsogetint esudh System out println CS parent is parent affected stmt executeUpdate INSERT INTO sensor values null 4 sensortype N null parents U bpendinc if affected 1 System out println A sensor of a CS was added to the database else System out println A sensor of a CS was not added to the database else if scsname null 4 TS SENE executeQuery SELECT scsid from scs where scsname scsname while rs next parent rs getint sesid
16. A RoleRequestMsg is sent to the OK OK instantiated SCSManager b A SCSSession actor is created OK OK and responds to the CSAgent c All SCSAgents receive OK Failed notification of the new SCS d The new SCSAgent receives OK Failed setup parameters and a list of SCS e The CSSession actor receives OK OK notification of the new gent f The database is updated with the OK OK new SCS 3 A GPS a The sensor is detected and a Failure not Failure not receiver is SensorA gent is initiated implemented implemented connected b The sensor receives a specific OK OK the SCS SensorAgent and polling of data is initiated c The SCSAgent is notified of the OK OK new sensor 136 5 SCG A Distributed Sensor Management Network in ActorFrame d The CSAgent is notified of the OK OK new sensor and initiates a timer e The MSAgent is notified of the OK OK new sensor and initiates a timer f The database is updated with the OK OK new sensor As seen in point three of the table the SensorDetectionEdge actor does not provide automatic sensor detection as of yet and thus cannot provide the service expected The SensorDetectionEdge actor implemented does nothing more than wait a determined time interval before reporting a gps receiver detected on port COM12 b Testing sensor updates This test was conducted for testing the sequence diagrams i
17. 1 1 1 i connectionTimer PCSDown K k ECSInit SCSPCSFailed mySCSS InitECS SCSPCSDown f SCS reporting in ECS mode Figure 8 41 The sequence diagram for a failed PCS between a SCS and CS A missed receipt signal is in this case interpreted as a communication failure Alternatively a failure could be interpreted as a certain number of missing receipts Each time the connectionTimer was received a connection counter could be incremented and at a certain counter value the ECS could be assumed down The failure of the link could affect the report status of the control agent but if capacity of the new link is capable operations could continue as normal So if the connectionTimer expires before the SCSReportReg signal is received the SCSRouter assumes that the PCS link is down The SCSRouter actor subsequently alerts the SCSControlAgent actor of the failed link so it can adjust to the new status shown later SCSRouter actor also sends a request to the OSAPIEdge actor to initiate the reserve communication link through the signal nitEcs Upon confirmation that the ECS has been initiated SCSRouter sends the SCSPCSFailed signal to its CS node s CSSession alerting that the PCS has failed The CSSession actor can then handle the further situation by both being a recipient of alarms from the SCS alerting S
18. Dataoverfering VHF en Teknisk Ukeblad tu no viewed 3 7 2006 URL http www tu no nyheter ikt article53380 ece wimax com Frequently asked questions FAQ viewed 15 6 2006 URL http www wimax com education faq Conversation with Frode Flegstad Telenor R amp D Trondheim 11 7 2006 PaloWireless Bluetooth Resource Centre Bluetooth tutorial Specifications viewed 7 4 2006 URL http www palowireless com infotooth tutorial asp S S Kristiansen Transparent communication over Bluetooth Project Thesis ITEM Ericsson NTNU Autumn 2005 5 S Kristiansen Bluetooth enabled Peer2Peer services in ActorFrame Master Thesis ITEM Ericsson NTNU Spring 2006 ZigBee a technical overview of wireless technology viewed 3 7 2006 URL http zigbee hasse nl 129 5 SCG A Distributed Sensor Management Network in ActorFrame 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 Brombach Spar enorm utbredelse av Zigbee digi no viewed 3 7 2006 URL http www digi no php art php id 112409 J Rumbaugh I Jacobsen G Booch The Unified Modeling Language Reference Manual Second Edition Addison Wesley 2006 ISBN 0 321 24562 8 G Melby K E Husa ActorFrame Developers Guide NorARC ARTS September 2005 Haugen B Moller Pedersen JavaFrame FrameWork for Java Enabled Modelling Ericsson Research No
19. NTNU Innovation and Creativity Sea Cage Gateway A Distributed Sensor Management Network in ActorFrame Jens Martin Breivik Askgaard Master of Science in Communication Technology Submission date August 2006 Supervisor Rolv Br k ITEM Co supervisor Frode Fl gstad Telenor Research Norwegian University of Science and Technology Department of Telematics Problem Description The Sea Cage Gateway SCG project is about remote management administration and surveillance of offshore fish farming facilities Each facility consists of many sea cages and usually an adhering feed barge Several factors are changing in the traditional location for these facilities Amongst these are the environmental threats that sea cages can pose for a delicate coastal environment When such installations are moved further offshore the need for remote management will increase A certain degree of autonomy and self control is required by the sea cage installation The basis for this will be the use of sensors connected to the sea cages which report in to a computational device on each sea cage and further towards land This thesis studies how sensors can be integrated into the system in a flexible and dynamic way The system will require a variety of sensors and sensor data Some examples of sensor data are temperature current position sea cage status light etc The analysis should consider these requirements Furthermore due to the isolated po
20. System out println SCS parent is parent affected stmt executeUpdate INSERT INTO sensor values 1111 sensortype U N parente null Pending values 1 1 146 SCG A Distributed Sensor Management Network in ActorFrame System out println A sensor of SCS was added to the database else System out println A sensor of SCS was not added to the database catch Exception System out printin Problem toString finally try stmt close catch Exception Eystem out prriHbln s stmt nuli Fre conet eum try con close catch Exception e System out prrHbln s tostringt con null Hh public void updateSCSCommLinkECS String scsname throws Exception Connection con null Statement stmt null int affected 0 try String url Jdbe mysql scgdb Class forName com mysql jdbc Driver newInstance con DriverManager getConnection url user komtek stmt con createStatement affected stmt executeUpdate UPDATE SCS SET commlinkid 3 where scsname scsname Nnm System out println The SCS comm status has been updated else System out println The SCS comm status has not been updated catch Exception System out pran
21. etsensor Update ScscaToSm PositionAlert pnsorUpdateTimer amp PSSensorData PCSRestored ScscaToScsr ScscaToSm ScscaToScsr m cM 161 SCG A Distributed Sensor Management Network in ActorFrame OSAPIAgent RoleRequestMsg waitEdgeConf RoleConfMsg WindowsAPIEdge The port WapieToR is connected to the SCSRouter PCSRestored SensorManager The port SmToScsca is connected to SCSControlAgent NewSensor GetSensorUpdate PSSensorData NewSensor PSSensorData via GetSensorUpdate 162 SCG A Distributed Sensor Management Network in ActorFrame GPSSensorAgent NewSensor SetSensorUpdate PSSensorData NewSensor NewSensor NewSensor GPSControlAgent The port GpscaToGpsse is connected to the GPSSensorEdge actor and the port GpscaToDel is connected to the SCSControlAgent monitoring gt gpsUpdate SPSPositionUpdate etSensorUpdate ResetDefaultGPSPosition gpsUpdate a eq vi GpscaToGpsse idle SPSPostionUpdate monitoring M d true GPSPositionUpdate monitoring Distance gt threshold PositionAlert via GpscaToDel GPSSensorEdge The port GpsseToGpsca is connected to the GPSControlAgent ReqGPSPosition PSPositionUpdate via GpsseToGpsca 163 SCG A Distributed Sensor Management Network in ActorFrame b CSAgent
22. A Distributed Sensor Management Network in ActorFrame Fish farm overview Mozilla Firefox File Edit Go Bookmarks Tools Help lt a A http flocalhost 8080 scgstatus jsp Sensor name Sensor value GPS 6325 3545 1026 2311 E Figure 9 15 A screenshot of SCG system web interface This web interface also detects changes in the status of the SCS node and alters the colour of the element when the status indicates it For this demonstration a deviation in the GPS position sets the status of the SCS to yellow This is shown in Figure 9 16 Sensor name Sensor value GPS 6325 3495 N 1026 2996 Figure 9 16 The SCS status has been set to yellow A PCS failure with the corresponding ECS initiation sets the SCS status to red and updates the CommLink field to ECS This is shown in Figure 9 17 Status Commlink scgsicsalesr CSRouer OK MCS SCS Status Commlink Iscgslesalscsmilscgs scsa scsr SCSSession RED ECS Sensor name Sensor value GPS 6325 3495 N 1026 2996 E Figure 9 17 The SCS status has been set to red and ECS has been initiated 103 SCG A Distributed Sensor Management Network in ActorFrame Otherwise the status of the SCS has been set to green Since there are no sensors connected to the CS in the demonstrator and the CS does not experience any communication link failures its status is by default always green But
23. Initiating the connection between a new CS and MS The first step of setting up the system is for a new CS node to contact and register with its MS node A RoleRequestMsg signal is therefore sent from the CSRouter actor of the CS node to the MSAgent inner actor CSManager and requests a CSSession actor to coordinate further interaction with The sequence diagram for this procedure is shown in Figure 8 22 sd A new CS registers with MS csr CSRouter scsm SCSManager csm CSManager dbe DBEdge RoleRequestMsg mylD CSSession l o lt lt create gt gt _ myID CSSession RolePlayMsg RoleConfMsg I 1 RegisterCSInfo sensors capabilities myCSA CIA UpdateCSList myCS capabilites AddCSToDB csname msname AddCSToDB csname msname 2 Registered yourMS CSList 1 CSList updatedCSList C RegisterMS myCSS 9 n o SSeS 4 gt SetupParameters parameters tupParameters parameters Figure 8 22 The sequence diagram for new CS registering with MS Upon reception of the RoleConfMsg signal the CSRouter actor registers with its designated CSSession actor with the RegisterCSInfo signal a signal containing information about the CS In demonstrator this signal is empty CSSessio
24. SCS node The CS node administrates and controls all SCS nodes contained within the frame of the CS node CS node The CS node may have to be aware of the other CS nodes under the same MS node to enable further functionality such as resource sharing or additional redundancy MS node The CS node interacts frequently with the MS node and generated reports and alarms are sent to this node PCS The PCS must be handled by the node This includes both the initiation of the link and the checking of its status MCS The CS node must also maintain and supervise the MCS link with the MS node FCS The node must be aware of its FCS and have the ability to initialize it and utilize it It must also be aware of the link characteristics and adjust to these accordingly One such characteristic could be data rate another could be latency Mobile Each SCS node should provide the possibility for a direct connection terminal via a mobile terminal present at the SCS 48 SCG A Distributed Sensor Management Network in ActorFrame The CS node tasks are largely similar to the SCS node tasks listed previously Besides these the CS node may need to provide larger database requirements The CS node may also require interoperability with more equipment for instance the feeding technology For the time being this function is regarded as one of the sensors 8 2 3 The MS node The MS node represents the main computing environment of the SC
25. SCSAgent Figure 8 2 System cardinality and connections 40 SCG A Distributed Sensor Management Network in ActorFrame Here the relative connections implied by the proposed communication schemes are illustrated These relations have a significant influence on system design and come up again when analyzing the environments of the system elements As a basis for design the system also assumes a certain setup sequence As shown in Figure 8 3 the MS node with its MSAgent actor is the first node to be set up Then the CS node is set up and when the CSAgent actor is initiated it proceeds to register Itself with its MSAgent Figure 8 3 How the SCG system is created Finally the SCSAgents are created and register with their CSAgent who in turn reports the presence of a new SCS node to its MS node It is therefore assumed that a MS node exists before a CS node is initiated The Register Confirm procedure corresponds to the RoleRequest protocol of ActorFrame The SCG system should allow for extensions to be added with a fair amount of ease incorporating additional services with new actors and roles An example of this is shown in Figure 8 4 where a mobile device receives SCG information and could provide control functions for the systems administration 41 SCG A Distributed Sensor Management Network in ActorFrame SC 24 1 Alesund 30 03 2006 Temperature 14 C 21 C Wind 14 knots Direction
26. csa csr CSRouter If however message is sent from the aforementioned ActorAddress via ActorRouter to a distributed actor where the method getSenderRole is applied on the received signal a different result is generated Now the address is IP address csa csr aQ CSRouter 109 SCG A Distributed Sensor Management Network in ActorFrame This quickly caused inconsistencies in the database and had to be considered and taken into account during the subsequent system design 110 SCG A Distributed Sensor Management Network in ActorFrame 10 Discussion In this chapter the content and experiences from this thesis are discussed and presented New features and areas future work are also presented 10 1 Experiences from deployment of demonstrator During the design implementation and testing of the SCG system some problems were discovered and issues were unearthed The following sections summarize the different aspects of the SCG system and discuss some changes or adjustments that could be made to the system design modelling tool and the ActorFrame framework 10 1 1 ActorFrame in the SCG domain ActorFrame provides state machines signal interaction and play concepts to support the services required by the SCG system The plays given are system setup system communication alarm generation and link failure handling and together provide a distributed sensor data retrieval network with link redunda
27. else 150 SCG A Distributed Sensor Management Network in ActorFrame System out println The SCS status has not gone to red catch Exception System out printin Preblem finally seme nuli f try stmt close catch Exception e System out printin e tostring 7 semt nuli Cone con close catch Exception e System out printin e tostming 0 con public void setScsStatusGreen String scsname throws Exception Connection con null Statement stmt null int affected 0 try String url Jdbe smysql scgdb Class forName com mysql jdbc Driver newInstance con DriverManager getConnection url user komtek stmt con createStatement affected stmt executeUpdate UPDATE SCS SET statusid 1 where scsname scsname arcectced System out println The SCS status has gone to green else System out println The SCS status has not gone to green catch Exception e System out printin Preblem toString finally if muli f iy ud stmt close catch Exception System printin stmt null cone num try con close catch Exception System out prinblin e tostring Con
28. javagps jar no ntnu item master2006 ext smsHandler se ericsson eto norarc actorframe jcoord 1 0 zip no ntnu item master2006 Contains the classes for none javagps jar ext GPSHandler interaction with the jeoord 1 0 zip GPS receiver RXTXcomm jar no ntnu item master2006 Contains the classes for none mysql ext mySQLHandler interaction with the MySQL database connector java 3 1 13 bin jar no ntnu item master2006 ext simpleAdminGUI Contains the classes for the GUI no ntnu item master2006 se ericsson eto norarc actorframe none no ntnu item master2006 ext sms Handler Contain the classes for interaction with the SMS server none axis jar commons discovery 0 2 commons logging 1 0 4 jar jaxrpc jar sms jar saaj jar wsdl4j 1 5 1 jar se ericsson eto norarc ac torframe Contains ActorFrame none actorframe2 0 0 2 jar 12 If problems are encountered please do not hesitate to send an e mail about it to jens askgaard com 133 SCG A Distributed Sensor Management Network in ActorFrame scsagent Contains the generated no ntnu item master2006 jcoord 1 0 zip code for MSAgent no ntnu item master2006 ext GPSHandler RXTXcomm jar actor no ntnu item master2006 ext mySQLHandler no ntnu item master2006 ext simpleAdminG UI no ntnu item master2006 ext smsHandler se ericsson eto norarc actorframe csagent Contai
29. lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt Figure 7 7 ActorFrame management console This screenshot shows the creation of a RoleRequestMsg signal to the SCGSystem actor requesting a CSAgent actor named The current status of 5 instance of the SCGSystem actor can be seen in the background The design of the SCGSystem actor is shown in section 9 5 7 2 2 3 ActorFrame routing system ActorRouter ActorRouter is part of the ActorFrame framework and provides support for the transparent distribution of actors Unfortunately no official documentation currently exists on how ActorRouter works or which services it supplies so the following description is given strictly from observing its behaviour and through a black box interpretation with elements of a trial and error process The ActorRouter requires the setting of a public IP address and a default gateway address The public IP address is necessary since ActorRouter uses application level routing This implies that the IP address of the sending party is included in the messages and not read from the IP header This requires that designers or users must have more knowledge about their network connection and topology than usual For ActorRouter is sometimes referred to as Actor router In t
30. seme cn try stmt close catch Exception e System out println e toString if con 1 puli con close catch Exception System con null public void addSCS String scsname String csname throws Exception Connection con null Statement stmt null int affected 0 ResultSet rs null int parent 0 try String jdbc mysqli sci Class forName com mysql jdbc Driver newInstance con DriverManager getConnection url user komtek stmt con createStatement rs stmt executeQuery SELECT csid from cs where csname csname nimm while rs next 4 parent essi System out println CS parent is parent affected stmt executeUpdate INSERT INTO scs values null parent 2 NO scsname nim execute updates returns number of affected rows ab System out println A SCS was added to the database else System out println A SCS was not added catch Exception e 145 SCG A Distributed Sensor Management Network in ActorFrame System out printin Problem e toString finally steme l null try stmt close catch Exception e System out print iln e tostring seme nuli con try con close
31. the feed necessary for the fish Sensors may be attached to SCG A Distributed Sensor Management Network in ActorFrame the control station Frame The frame is a boundary around the sea cages and keeps the cages together whilst yielding some protection against the elements A frame contains up to ten sea cages all which reside under the same control station Sea cage The Sea Cage station is the node directly attached to each individual station sea cage Each sea cage controls and administers the sensors SCS connected to it and reports sensor data and deviating values to the rest of the system Sensors Sensors form the basis of the system All sea cages consist of a basic array of sensors in addition to specialized sensors which are distributed among each farm Sensors are used to collect information for both optimizing breeding conditions in addition to surveillance and control of the sea cage status The size of a frame is minimum 500 x 200 metres which gives a sense of the range communications will have to traverse 1 In addition to the nodes of the system a wireless communication scheme has been developed It consists of two primary broadband communication links the Primary Communication System PCS and the Main Communication System MCS combined with two narrowband backup systems named as the Emergency Communication System and the Failure Communication System ECS and FCS Th
32. the relative alarms are issued and the status of the SCS is updated in the database The demonstrator to be implemented only has the use of a GPS receiver In the SCG system domain itself GPS is used mainly to detect sea cages drifting out of position This would only require reactive sensor polling on the GPS receiver to achieve its task But seen in the light of both context information and other parties interested in 77 SCG A Distributed Sensor Management Network in ActorFrame the GPS position of sea cages see Table 4 1 the GPS sensor has been implemented with hybrid sensor polling The generic signal SensorData has been replaced with GPSSensorData and the Sensor ValueDeviation signal has been replaced with a PositionAlert signal When the position received from the GPS receiver violates the maximum position deviation threshold a PositionAlert signal is propagated throughout the SCG system alerting all involved actors of the status updating the SCS status in the database and SMS alarms are generated to the rescue team This is shown in the communication diagram presented in Figure 8 40 comm The SCS registers a position deviation 1 4 PosAlertForSCS _ Database 1 Polling SensorManager x MSAgent Sensor poe 1 1 PositionAlert 4 3 PosAlertForSCS 1 5 PosAlertForSCS SMS Server 1 2 PositionAlert SCSAgent CSAgent Figure 8 4
33. 14 SCG A Distributed Sensor Management Network in ActorFrame The AkvaSensor camera shown in Figure 4 1 is a camera for visually monitoring the sea cage stock The camera is adjustable for both depth and position and provides high resolution video for fish and feed surveillance 13 Figure 4 1 The AKVAsmart AkvaSensor Camera SmartEye 13 The AkvaSensor Biomass Estimator equipment is shown in Figure 4 2 This system utilizes camera images to estimate the biomass in the sea cage based on biomass distribution knowledge 14 Figure 4 2 The AKVAsmart AkvaSensor Vicass Biomass Estimator 14 The AkvaSensor Oxygen equipment is shown in Figure 4 3 This sensor is used to monitor oxygen conditions in the sea cage 15 Figure 4 3 The AKVAsmart AkvaSensor Oxygen 15 There are of course many other sensors and producers of equipment This is just meant as an introduction to the variety of sensors a SCG system must be able to incorporate and utilize to their full potential 13 SCG A Distributed Sensor Management Network in ActorFrame 4 3 Sensor networks A sensor network is a computer network consisting of many distributed sensors all registering and reporting data either to each other or to a centralized computing unit A sensor network consists of three elementary parts sensing communication and computation 16 Figure 4 4 A sensor network
34. 17 Sensor networks are currently being utilized in several application areas such as traffic surveillance air traffic control cars robotics and environmental monitoring Their application domain is steadily increasing mostly due to the constant development of cheap low energy high capability sensors There are many challenges concerning the use and deployment of sensor networks The limiting factors of a sensor network are energy conservation limited computational and memory resources and bandwidth requirements In light of these issues several types of sensor networks are implemented with three main categories proactive reactive and hybrid 18 Note that these sensor networks are assumed to be made up of homogeneous sensors Although this is not the case for the SCG system which will incorporate many different sensors the theory of sensor handling still applies Proactive In a proactive sensor network sensors sense and send their data at pre determined intervals of time These sensor networks are often used in areas were periodic examination is the area of interest The interval between transmissions can be manipulated according to needs A longer interval will translate into fewer transmissions and lower power use However the information density will be correspondingly poorer With a shorter polling interval the power consumption will increase but so will the information amount retrieved 18 This type of sensor data a
35. 2002 2003 131 SCG A Distributed Sensor Management Network in ActorFrame URL http jgroup sourceforge net download JgroupARM pdf 132 SCG A Distributed Sensor Management Network in ActorFrame Appendix A User manual Here instructions on how to test the simulated system are described The implementation of the system can be found in the zip file uploaded with this thesis This user manual assumes the use of the same GPS reciever and GPRS modem with the same subscripition Djuice 1 In order to try test the demonstration or eventually perform changes needs to download the Eclipse Platform version 3 1 2 from http www eclipse org 2 Following the instructions for installing Ramses from the Ramses Wiki available from http www item ntnu no lab pats wiki index php Ramses User Page 3 Choose Import gt Existing Projects into Workspace and import the zip file no ntnu item master 2006 on the accompanying zip file specified in Appendix I It is usually a good idea to restart the work area at this point 4 The projects imported and their project and external JAR dependencies are show in Table A 1 Table A 1 System projects with dependencies Project Description Dependencies no ntnu item master2006 Contains the files Projects JAR generated through the no ntnu item master2006 ext GPSHandler adminGUI jar system design tool no ntnu item master2006 ext mySQL Handler
36. 6 gt lt 7 gt lt 8 gt lt 9 gt M lt 10 gt M lt 11 gt lt 12 gt lt 13 gt lt CR gt lt LF gt The fields correspond to points displayed in Table 9 2 Table 9 2 The data of the GCA message 53 Field Example Description 1 104549 04 UTC time in hhmmss ss format 000000 00 235959 99 2 2447 2038 Latitude in ddmm mmmm format Leading zeros transmitted 3 N Latitude hemisphere indicator North S South 4 12100 4990 Longitude in dddmm mmmm format Leading zeros transmitted 5 E Longitude hemisphere indicator E East W West 6 1 Position fix quality indicator 0 position fix unavailable 1 valid position fix SPS mode 2 valid position fix differential GPS mode 7 06 Number of satellites in use 00 12 8 01 7 Horizontal dilution of precision 00 0 99 9 9 00078 8 Antenna height above below mean sea level 9999 9 17999 9 92 SCG A Distributed Sensor Management Network in ActorFrame 10 0016 3 Geoidal height 999 9 9999 9 11 Age of DGPS data since last valid RTCM transmission in xxx format seconds NULL when DGPS not used 12 Differential reference station ID 0000 1023 NULL when DGPS not used 13 5C Checksum For more information on NMEA messages see 52 9 1 3 Reserve communication link The primary communication link MCS and PCS for the SCG system in this thesis is WLAN although
37. A MS was added to the database else System out println A MS was not added catch Exception e System out println Problem e toString finally stmt null try catch Exception System out println e toString simt nUll at try con close catch Exception e System out println e toString com null public void addCS String csname String throws Exception Connection con null Statement stmt int affected 0 ResultSet rs int parent 0 try 144 SCG A Distributed Sensor Management Network in ActorFrame string url Class forName com mysql jdbc Driver newInstance con DriverManager getConnection url user komtek stmt con createStatement rs stmt executeQuery SELECT msid from ms where msname msname nomm while rs next parent rs getInt msid System out println MS parent is parent affected stmt executeUpdate INSERT INTO cs values null parent Sn A csname execute updates returns number of affected rows affected 1 System out println A CS was added to the database else System out println A CS was not added catch Exception System out println Problem e toString finally 4 if
38. ActorFrame SCG A Distributed Sensor Management Network in ActorFrame List of figures FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU FIGU RE 2 1 FACTORS AFFECTING EXPLOITABLE STOCK REDRAWN AND SLIGHTLY MODIFIED FROM 3 4 RE 2 2 A RIGID SEA CAGE 4 test seven recette eere emo ce nics e e o pea eee E fedes 5 RE2 3 A FLEXIBLE SEA CAGE 5 recie ct tre tct nee ete ette e eee egere a etes E pete 5 RE 2 4 A MOBILE FEED BARGE BY A SEA CAGE 6 6 RE 2 5 THE SEAW ATCH SYSTEM OVERVIEW 9 7 RE 2 6 RADAR IMAGES USED FOR DETECTING AND POSITIONING FISH CAGES 10 8 RE 3 1 AN OVERVIEW OF THE SEA CAGE GATEWAY SYSTEM ELEMENTS 9 RE 3 2 COMMUNICATION SCHEMES OF THE SEA CAGE 10 RE 3 3 THE DRIFTING BOUNDARIES FOR SEA CAGE cccsssssscceceesessscesececsesesnsaeceeeesesennsaseeeeeeesensaaeas 12 RE 4 1 THE AKVASMART AKVASENSOR CAMERA SMARTEYE 131 15 RE 4 2 THE AKVASMART AKVASENSOR VICASS BIOMASS ESTIMATOR 14 15 RE 4 3 THE AKVASMART AKVASENSOR OXYGEN 15 essere 15 RE 4 4 A SE
39. Here the state machines of the inner actors of the CSAgent are presented CSRouter The port CsrToScsm is connected to the SCSManager and the port CsrToCsca is connected to the CSControlAgent The variable myCSS is an ActorAddress for the nodes CSSession waitForCcsConf CSRegistered CsrToScsm CsrToCsca RoleRequestMsg etupParameters CSList SGPSSensorData GPSSensorData waitForRoleConf as via idle ensorData vi RoleConfMsg CsrToCsca CsrToCsca j gt RegisterCSInfo TS 7GelSensorUpdate idle myCSS aaa GetSensorUpdate vi idle DpdateSCSCapabilites PosAlertForSCS tSCSSensorUpdate gt SCSPCSFailed pdate apabilte PosAlertForSCS via CsrToCsca PosAlertForSCS TO pdate myCSS TO myCSS e via CsrToScsm NewSCS p PCSRestored UpdateFinished NewSCS TO myCSS PCSRestored CsrToCsca SCSPCSDown gt idle 164 SCG A Distributed Sensor Management Network in ActorFrame CSControlAgent The port CscaToCsr is connected to the CSRouter actor osAlertForSCS rameters PSSensorData pdateSCSCapabilities SCSManager The port ScsmToCsr 15 connected to the CSRouter idle UpdateSCSList Upd
40. N NE Time 13 42 15 Position 39 3 76 6 W Status Operational Camera Figure 8 4 Preliminary illustration of mobile application interface Interaction for such an application could be achieved in a variety of ways This application could connect through a standard GPRS connection to the MS node or connect via Bluetooth as a part of an ad hoc network at the actual facilities at an SCS or CS node An alternative way of access for system interaction could be through the use of a web browser which allows for a standard and easy way to access information The use of web browser interfaces is steadily increasing with the advantage of a standardised and highly distributed interface However if the user is on location and wishes to retrieve information directly from a SCS or a CS this might be impractical This is due to the fact that if the CS is connected via a pay per data technology this could incur increased and unnecessary costs for the supplier Some possible functions will be illustrated in the design presented in the following sections but will not be implemented in the demonstrator for this project These functions are to illustrate further areas of application whilst the demonstrator is the focus for the implemented elements 8 1 4 basic set of functional requirements In order to aid the design and testing process of the SCG system some basic functional requirements for the system as a whole have been def
41. SENSOR 73 FIGURE 8 33 THE SEQUENCE DIAGRAM FOR RETRIEVING SENSOR DATA FROM A CS NODE S SCS NODES EP E 73 FIGURE 8 34 A HIGH LEVEL COMMUNICATION DIAGRAM FOR SENSOR DATA RETRIEVAL FROM SCS FIGURE 8 35 THE SEQUENCE DIAGRAM FOR A SCS RETRIEVING ITS SENSORS DATA FIGURE 8 36 THE SEQUENCE DIAGRAM FOR INTERACTION BETWEEN THE SCS AND ITS SENSORS FIGURE 8 37 THE SEQUENCE DIAGRAM FOR PROACTIVE SENSOR POLLING FIGURE 8 38 THE SEQUENCE DIAGRAM FOR REACTIVE SENSOR POLLING FIGURE 8 39 THE SEQUENCE DIAGRAM FOR HYBRID SENSOR POLLING FIGURE 8 40 A HIGH LEVEL COMMUNICATION DIAGRAM FOR ISSUING POSITION DEVIATION ALERTS 78 FIGURE 8 41 THE SEQUENCE DIAGRAM FOR A FAILED PCS BETWEEN A SCS AND CS FIGURE 8 42 A HIGH LEVEL COMMUNICATION DIAGRAM FOR WHEN A PCS FAILS FIGURE 8 43 THE SEQUENCE DIAGRAM FOR A FAILED PCS BETWEEN CS AND SCS FIGURE 8 44 THE SEQUENCE DIAGRAM FOR A FAILURE OF MCS BETWEEN MS AND 83 FIGURE 8 45 THE SEQUENCE DIAGRAM FOR A FAILURE OF MCS BETWEEN CS AND MS 84 FIGURE 8 46 THE SEQUENCE DIAGRAM FOR AN FCS FAILURE ceste FIGURE 8 47 A HIGH LEVEL COMMUNICATION DIAGRAM FOR A FAILED FCS FIGURE 8 48 THE SEQUENCE DIAGRAM FOR INTERACTION BETWEEN THE 5 5 AND MS IN ECS MODE 87 FIGURE 8 49 A HIGH LEVEL COMMUNICATION DIAGRAM FOR SENSOR REPORTING WITH ECS 87 FIGURE 8 50 A HIGH LEVEL COMMUNICATION DIAGRAM FOR POSITION ALERTS WITH ECS 88 FIGUR
42. Sea Cage Gateway system In this chapter the design of the Sea Cage Gateway system based on ActorFrame is presented First the elements environments and task of the nodes comprising the system are identified and described The actual design based on the elements identified so far in this thesis is presented and is followed by sequence and communication diagrams describing the actions and functionality of the system in different modes of operation 8 1 Design goals and considerations This thesis is to utilize the ActorFrame framework for providing the desired functionality of the SCG system In addition the design considers issues such as multiple communication links as well as looking to sensor networks and mobile grid for inspiration The system design is also inspired by many design principles listed in 48 Although these principles are mainly directed at the SDL domain they give many sound guidelines for modelling in the ActorFrame domain which resembles SDL in many ways Among the principles followed are describe the environment mirror the environment behaviour mirror the environment knowledge analyze the behaviour look for similarities and analyse the variability 48 These principles have all been applied to a varying degree In Figure 8 1 the distribution of the different nodes is shown and how the nodes forming the basis of the SCG system are meant to be interconnected An actor will represent each node of the system T
43. Sensor Management Network in ActorFrame 3 The Sea Cage Gateway project The Sea Cage Gateway is a project researching how to best control and administrate offshore and remote fish farming facilities The focus of the project is the use of wireless communication technologies to provide a flexible and adaptable framework for developing and implementing services for the system 3 1 Domain description In 1 a domain description has been provided as a basis for the system architecture The main components of the Sea Cage Gateway system have been defined as three main nodes sensors and four alternative communication schemes A high level overview is given in Figure 3 1 Sea Cage Gateway Sensors 4 amp Figure 3 1 An overview of the Sea Cage Gateway system elements 1 The main features are shown and described in Table 3 1 Table 3 1 The elements of the Sea Cage Gateway system Feature Description Management The management station is the land based administrative station for station MS all control stations All information collected by the elements in the Sea Cage Gateway system are handled and distributed by the management station Control Station The control station 15 the controlling agent of all the sea cages in a CS single frame The control station administers the sea cages represents the frame in the system and provides amongst other services
44. String commLinkStatus String UpdateCSList UpdateFinished UpdateSCSCapabilities sensorT ype String scsname ActorAddress Add code for serialization of scsname UpdateSCSCommLinkStatus scsname String commLinkStatus String UpdateSCSList newSCs ActorAddress UpdateSCSStatus scsname String status String 171 5 SCG A Distributed Sensor Management Network in ActorFrame 172 SCG A Distributed Sensor Management Network in ActorFrame Appendix Implementation The implementation of the demonstrator is available on the Appendixl zip file accompanying the delivery of this thesis The contents of this file are shown in Table I 1 Table I 1 The contents of Appendix I File Contents no ntnu item askgaard master2006 Scgsystem zip msagent csagent scsagent simulation no ntnu item master2006 no ntnu item master2006 ext GPSHandler no ntnu item master2006 ext mySOL Handler no ntnu item master2006 ext simpleAdminGUI no ntnu item master2006 ext smsHandler se ericsson eto norarc actorframe scgdb sql The scgdb database scgstatus jsp The web interface for the SCG system The LoggingServer class can be found in the no gps package of the no ntnu item master2006 ext GPSHandler project The SQLInterface class can be found in the no sq package of the no ntnu item master2006 ext mySQLHandler project 173
45. These are not alternatives for the communication links presented earlier but represent communication technologies which can incorporate other functionality relative to the SCG system 6 1 GPRS GPRS General Packet Radio Service is considered a 2 5G G for Generation technology with GSM being 2G and the aforementioned UMTS being 3G To use GPRS a mobile terminal or modem supporting it is required and an operator subscription including GPRS is necessary GPRS provides data rates of up towards 160 Kb s and the coverage map for Telenor GPRS in Norway is shown in Figure 6 1 400 km Figure 6 1 Coverage map for Telenor GPRS 25 As can be seen GPRS does cover many near coastal areas the orange areas and in certain areas it also covers offshore areas enabling the technology to be implemented 23 SCG A Distributed Sensor Management Network in ActorFrame at certain locations GPRS operates on restricted frequencies and requires locally installed infrastructure An improvement over the traditional GSM data is that GPRS 15 packet based and payment 15 for the data sent not the time connected In the SCG system GPRS is an alternative for the narrowband ECS and FCS communication links The stability and latency of a GPRS connection can be varying and pose a challenge for the application 6 2 CDMA450 450 is a new technology utilizing the old NMT network in Scandinavia and is provided by ICE AS i
46. a cheaper source of vital proteins for many groups of the human population Proteins are a high value source of nutrition not always easily accessible in under developed areas 2 2 Factors affecting aquaculture production There are many variables affecting the efficiency of aquaculture and the amount of biomass that can be extracted In Figure 2 1 the main elements and there co dependencies are shown Actually in the SCG domain the word pisciculture would be more accurate as this relates to the cultivation of fish Aquaculture is a more general term including all forms of marine life Aquaculture will nonetheless be used for the remainder of this thesis SCG A Distributed Sensor Management Network in ActorFrame environmental recruits growth 7 rate recruitment rate reproduction 4 egg survival fry survival and a growth competition pre recruit survival for food exploitable stock and growth biomass L5 enviromental fishing mortality factors rate disease t senescence natural mortality 4 yield to humans rate management predation Figure 2 1 Factors affecting exploitable stock redrawn and slightly modified from 3 As shown there are many factors affecting the efficiency of fish stock rearing From the fish are fry until they are ready for harvest many growth environment conditions affect their development Improving these conditions to maximize pr
47. all of these sequence diagrams have been implemented and in some of the diagrams generic signal names are used This is commented in the subsequent sections A full list of signals and parameters can be found in Appendix H 8 4 4 Setting up the system Before being able to provide the services necessary for the Sea Cage Gateway system the system must be set up and the nodes must be connected The system set up is designed with two main objectives the distribution of the necessary addresses for interaction and to allow for easy configuration and set up for new nodes attaching to the current system The setup also establishes the hierarchy of inter communicating actors The actors involved in collaborations between the distributed nodes are shown in Figure 8 21 cs1 CSSession cs2 CSSession cs3 CSSession csr1 CSRouter csr2 CSRouter csr3 CSRouter scss11 SCSSession scss12 SCSSession scss21 SCSSession scss31 SCSSession scsr11 SCSRouter scsr12 SCSRouter e MSAgent e CSAgent a SCSAgent Figure 8 21 The intercommunicating actors of the SCG system 63 SCG A Distributed Sensor Management Network in ActorFrame To allow for easy configuration the SCG system is assumed to be set up with the MSAgent first with subsequent CS nodes attaching later This also applies to the SCS nodes later connected to their CS node This is shown in Figure 8 3 Finally sensors are attached to the SCS node 8 4 1 1
48. as the ECS only to the CS node This reduces the load on the MS node in the event of a large scale PCS failure In the case of an FCS failure ECS is used as previously suggested The BCS solution is dependent on the type of address the CS node has private or public and how much of a cost is put on the MCS link But it is an addition to be considered Otherwise an optional design of the SCSAgent and CSAgent can be considered The alternative design is shown in Figure 10 2 116 5 SCG A Distributed Sensor Management Network in ActorFrame SCSAgent lt lt Actor gt gt 0 1 Mobile Terminal Router Figure 10 2 Alternative SCSAgent design Here the SensorManager actor is no longer connected to the SCSControlAgent actor but directly to the SCSRouter actor This design maintains the patterns of the higher level actors CSAgent and MSAgent where there lower level actors are independently connected to the router actor on the node CSManager actor and SCSManager actor relieving the ControlAgent actor of some signal traffic and providing easier access to the elements of the system The change shown in Figure 10 2 also applies for the SensorManager actor of the CSAgent actor The issue of providing globally amongst the SCG elements unique addresses for the actors of the system has not been addressed To provide full node access and interoperability all actors should have a unique address But since the amoun
49. boundary where a considerable strain on the moorings is necessary to achieve such a position Within the yellow boundary is the natural position of the sea cage where room to move with the current and tide has been given Finally the red boundary indicates that one or more moorings have broken and that there is a possibility of the cage being adrift The boundaries will have to be adjusted to the positioning of the GPS receiver on the sea cage as it is unlikely that the receiver will 12 SCG A Distributed Sensor Management Network in ActorFrame be mounted in the centre The alarm generated may take many forms and several could be used at once This could be e mail SMS call up function WAP Push application alarm to mention a few In the event of a communication failure the system will detects and handle the break and gives an alarm so a maintenance crew can be sent Meanwhile the system continues to operate and monitor the fish farm taking into the consideration the new situation the SCS node is in The main keywords are self configuration ease of use autonomy sensor handling self monitoring and fault tolerance 3 2 Previous work on the SCG As mentioned there have been projects concerning the SCG system previously These have explored and described the domain in question and demonstrated some possible functions 1 proposed and used a client server architecture between the nodes and utilized Web Services f
50. c 1 Message Receiver Actors 10 Message Receiver 7 Message Receiver Actors 5 a a 129 xx xx 01 4 Message Receiver a c 9 Add a c 129 03 3 Add a a 129 xx xx 01 2 Message Receiver a c 8 Message Receiver a a Figure 7 9 The workings of ActorRouter Upon receiving messages from foreign actors ActorRouter registers their origin and adds it to the local routing table When the actor receives the message in action six it replies to the sending actor As can be seen from the figure the local ActorRouter now has this actor in its forwarding table and the signal is sent directly to the correct domain action 8 These entries are removed after a certain time period if no more signals are sent or received The messages sending the visible resident actors of an ActorRouter are sent over a UDP connection whilst other messages are sent over a TCP connection ActorRouter is currently being extended to support Bluetooth interaction 37 38 ActorRouter does not support ports or connectors over distributed entities 7 2 3 ServiceFrame ServiceFrame is an application of ActorFrame designed to increase the abstraction level of service design The main objective as stated in 45 is The main objective of the ServiceFrame project has been to address the principal underlying problems seeking to provide sound and viable solutions that enable rapid developme
51. could have been used JSP provides the possibility of incorporating Java code with HTML tags For more information on JSP see 64 PHP is another high level tool for creating dynamic web content For more information on PHP see 65 AJAX represents a changing paradigm in web application development It combines the existing web technologies JSP DOM CSS and XML to provide a richer user interface and experience comparable to desktop applications AJAX functions more as an application than a web page on the client machine This application only retrieves information that is new to the browser when necessary instead of reloading pages to register changes For more information on AJAX see 66 The choice of JSP for implementing the web interface was largely due to the Java element of JSP thus using Java for both ActorFrame and JSP The web interface could later be extended to interact with ActorFrame classes if such functionality is wanted The web interface implemented regularly queries the database of the SCG system displaying the results in organized tables Every ten seconds the interface searches through the database and updates the web page with new elements and data Each registered MS node has its CS nodes under it with each CS having their SCS nodes displayed underneath them Finally the SCS sensors and values are displayed with their corresponding values A screenshot of the layout is shown in Figure 9 15 102 SCG
52. createStatement String query SELECT FROM MS rs mssql executeQuery query gt TABLE BORDER 2 bgcolor silver gt lt while rs next gt lt TD gt lt String st rs getString MSNAME gt lt 2 gt lt out printin st 155 SCG A Distributed Sensor Management Network in ActorFrame gt lt 2 gt lt query select csid csname statusname commlinkname from cs status commlink where cs statusid status statusid and cs commlinkid commlink commlinkid and cs msid msid csresult cssql executeQuery query while csresult next 55 lt TABLE BORDER 2 gt lt TR gt lt TH gt CS lt TH gt lt TH gt Status lt TH gt lt TH gt Commlink lt TH gt lt TR gt lt String s csresult getString CSNAME String tcs csresult getString statusname String rcs csresult getString commlinkname gt lt bgcolor lime align center gt lt TD gt lt out 5 S gt lt TD gt lt gt lt TD gt lt out printlin tcs TD TD 0ut println rcs TD TR TABLE csid esresule String newQuery Select scsid scsname statusname commlinkname from scs status commlink where scs statusid status statusid and scs commlinkid commlink commlinkid and scs csid csid scsresults scssql executeQuery newQuery while scsre
53. defined threshold values b The system must issues warnings regarding OK OK failed communication links and nodes As can be seen from the table some elements were not implemented mostly due to a lack of equipment but some due to that the development platform became increasingly unstable as the SCG system grew in size In addition it was discovered during deployment that ActorFrame uses its own serialization methods when sending ActorMessages over distributed links Theses methods do not support ArrayLists which were implemented as the means of registering lists of SCS nodes and CS nodes and subsequently distributed to the other nodes ActorFrame does support the serialization of Arrays but support for creating arrays as signal parameters or actor variables seems to be lacking in Ramses 9 5 2 Main experiences from testing Several discoveries were made during the testing process in addition to those that had a direct implication on the functional requirements specified In some cases this lead to the introduction of a new actor in other cases the logic had to be redesigned The main discoveries are briefly introduced below Initially it was intended to have the GPRS link initiated all the time and allow the operating system to use it when the LAN connection disappeared By appointing 108 SCG A Distributed Sensor Management Network in ActorFrame lower metrics in the routing table to the GPRS link it was assumed th
54. node Each SCS node will have a designated CS node to which it will report sensor data and other relevant information SCS node The SCS node may have to be aware of the other SCS nodes under the same CS node to enable further functionality such as resource sharing or additional redundancy PCS The PCS must be handled by the node This includes both the initiation of the link and the checking of its status ECS The node must be aware of its ECS and have the ability to initialize it and utilize it It must also be aware of the link characteristics and adjust to these accordingly One such characteristic could be data rate another could be latency Mobile Each SCS node should provide the possibility for a direct connection terminal via a mobile terminal present at the SCS 46 SCG A Distributed Sensor Management Network in ActorFrame The communication schemes should in essence be transparent for the application running on the SCS node and the type of communication link should only affect which entity the node contacts MS or CS Unfortunately this is not the case as a switch in communication link also yields a new connection with a new assigned IP address Since ActorRouter uses application level routing this will be handled by the node under the different failure modes A change of communication link also leads to a change in the recipient of signals as these are now supposed to be sent to the MS node In addi
55. not be received by the SCSRouter actor for the duration of the link failure But when the PCS has been restored again under the assumption of the SCS node receiving the same IP address this signal will be 88 SCG A Distributed Sensor Management Network in ActorFrame received by the SCSRouter This will indicate to the SCSRouter that the PCS is back online and that the GPRS connection can be taken down It can subsequently produce a response signal to the SCSSession actor who in turn can notify the rest of the SCG system that the link has been restored This has not been implemented as it has been assumed that a service team is necessary for restoring link failures thus the PCSRestored signal is generated by this team It is however an interesting concept for connections which can sometimes fall out without the link actually having failed 89 SCG A Distributed Sensor Management Network in ActorFrame 9 Implementation and deployment In the following chapter the implementation specific parts of the system are presented and described and the deployment of the system is described A test summary for the demonstrator is also given The system has been implemented on three different machines emulating a CS node MS node and the SCS node respectively These machines vary in type specifications capabilities and operating systems from a modern laptop via an industry computer to an older machine running L
56. of previously deployed cages 20 SCG A Distributed Sensor Management Network in ActorFrame 5 Grid computing With constantly increasing bandwidth capacity and connected nodes the border between remote and local entities are becoming blurred The possibility of accessing other resources on a network has led to the development of new techniques and architectures utilizing the availability of processing power and storage capacity This is often referred to as grid computing There are many different definitions of what grid computing really is One definition is given by 22 Grid is a type of parallel and distributed system that enables the sharing selection and aggregation of geographically distributed autonomous resources dynamically at runtime depending on their availability capability performance cost and users quality of service requirements The utilization of resources connected to a network has been exploited in several projects over the last decade taking advantaged of unused capacity present on idle connections Large complex tasks are split into small independent work tasks and are distributed among the participants of the grid This has been used to compute results on protein folding financial modelling earthquake simulation and climate and environment analysis 23 A vision of the future of grid computing draws parallels to today s power grids an inspiration which actually coined t
57. plays will largely consist of interacting actors placed on the nodes of the system The framework provides the addressing ports and connectors used for the system and handles message passing 7 2 2 2 ActorFrame standalone app and management console An ActorFrame standalone version has been released to enable quicker development and execution of services In essence this implies that developers do not have to use J2EE servers to execute services This is an advantage as dealing with J2EE servers can be a quite complex and heavy process 42 It should be noted that one can switch to J2EE platform at a later stage 42 ActorFrame also provides a management console which can be initiated upon service execution The management console provides many options from requesting the state of any actor to the sending of any signal available in the system In this project the 33 SCG A Distributed Sensor Management Network in ActorFrame management console has mainly been used for testing and debugging the system created A screenshot of the management console is shown in Figure 7 7 RoleRequestMsg Setactor type 5 05 v Log to file y Create act X 7 reate actor message t3 Status Select constructor RoleRequestMsg String String Actor type Actor id Specify input gt gt gt gt gt gt gt gt gt gt gt java lang String lt lt lt lt l
58. standard for wireless radio communication between nodes and access points 28 The standard is currently available in three versions 802 11a 802 11b and 802 11g The different versions operate at different frequencies and have different range and bandwidth capabilities The range of a WLAN signal from an access point depends on many factors Obstacles interference and power are critical factors which determine possible range Range can be boosted with added power or through the use of relay points The data rate for the 802 11g standard has for instance a theoretical maximum of 54 Mbit s but in reality it operates between 10 and 20 Mbit s To set up WLAN zone for communications one needs a wireless router access point and a terminal needs a WLAN client device The client automatically detects WLAN presence and can automatically set up a connection if the user wishes to As an alternative for the PCS WLAN is a clear potential candidate A WLAN network could be installed on each sea cage installation with a wireless router placed on the CS The wireless network is easily configured and setup data rates are high equipment is cheap and it is a well tested communication scheme The range depends on the equipment used and the power applied Standard wireless routers provide up towards 100 metres somewhat short of what is necessary Range can be improved by boosting antenna power or using relay points for re amplifying the signal Theoretic
59. the database does provide both alternative statuses and communication links for the CS as well The interface could have implemented much more information and functions but as the purpose of it was purely for simulation and demonstration no more functionality was added The full code of the web interface name scgstatus jsp is available in Appendix E To run the web interface a web server has been set up The web server used is the Blazix application server which is freely available under their own license definitions 67 This server is a high performance Java based server which can function both as a web server and as an EJB server application server In other words ActorFrame elements can be moved over to this server should the need arise The choice of this server is mostly coincidental there are many freely available servers that can be used Blazix is a small efficient Web Server suitable for this demonstration That it is written in Java is not a disadvantage for the cross platform interoperability For more information on the Blazix server see 68 9 4 Setting up the demonstrator The node computers were all connected to a LAN for testing LAN is used only since two of the computers used for the demonstrator did not support WLAN Compared to WLAN the SCG system will not behave any differently In addition it is easy to simulate a connection failure the Ethernet cable is simply pulled out The demonstrator was set
60. the scs table To create the status table To create the sensor table To create the sensortype table 142 SCG A Distributed Sensor Management Network ActorFrame To create the commlink table If preferable the scgdb database can be imported and is provided as part of Appendix I To import the database write The remaining queries used for interaction with the scgdb database can be seen in Appendix D and Appendix E 143 SCG A Distributed Sensor Management Network in ActorFrame Appendix D The SQLInterface class This appendix presents the code of the SOLInterface class used by the DBEdgeSM class to provide interconnectivity with the installed database of Appendix C Each method creates its own connection to the database and closes it when finished This has been done to avoid connection problems and overloads package no sql import java sql public class SQLInterface public void addMS String msname throws Exception Connection con null Statement stmt null int affected 0 try String url Class forName com mysql jdbc Driver newInstance con DriverManager getConnection url user komtek stmt con createStatement affected stmt executeUpdate INSERT INTO ms values null 1 msname execute updates returns number of affected rows if affected 1 System out println
61. this is an ActorFrame hardware or operating system problem is not clear The lack of flexibility for assigning the default gateway is also an area that can be extended Due to possible communication link failures access to a default gateway may be lost The possibility of assigning several default gateways in weighted orders would improve the redundancy handling of the system In the demonstrator this has been solved by issuing time interval generated messages to keep a fresh backup address present in the local ActorRouter s forwarding table During the testing phase of the demonstrator it was discovered that ActorFrame does not seem to support the sending of ArrayLists between distributed actors Using its own serialization method ArrayLists are not one of the parameters supported for signals This was unfortunate since ArrayLists were used to provide the lists of available SCSAgents and CSAgents As commented earliar ActorFrame does support Arrays but it does not seem as Ramses supports the creation of Arrays an unlucky combination There are alternative means of distributing the lists of available actors Strings could be written and parsed XML could provide structurally ordered information or a separate signal could be sent for each new actor but such complexity should be easy to avoid 112 5 SCG A Distributed Sensor Management Network in ActorFrame The inconsistency of the ActorAddresses retrieved through different met
62. to the wireless medium could to a degree be handled by the application By querying for instance the individual SCS one at a time in a round robin fashion for reports contention for the wireless medium is avoided thus reducing interference However signals should still be sent when reporting incriminated threshold values The routing theories of mobile ad hoc sensor networks could be of interest for handling inter node communication protocols between individual SCS nodes but this is beyond the scope of this thesis 4 3 2 Sensor Webs An extension of the mobile ad hoc sensor networks a sensor web incorporates more functionality in the sensor network mobile or fixed A sensor web as defined by NASA consists of a system of intra communicating spatially distributed sensor pods that can be deployed to monitor and explore new environment 20 A sensor web can consist of several sensors and platforms these can be orbital remember this is NASA s definition terrestrial fixed or mobile This is shown in Figure 4 5 18 SCG A Distributed Sensor Management Network in ActorFrame SENS Figure 4 5 The generalized concept of sensor web 21 The ability to create functioning sensor webs are due to the continuing progress of high performance low cost mobile sensor units Information collected by sensors are not simply sent to end users but propagated through th
63. uN int g while b 1 s Character toString char b 158 SCG A Distributed Sensor Management Network in ActorFrame 159 SCG A Distributed Sensor Management Network in ActorFrame Appendix G State machines In this appendix the state machines of the SCG system are presented They are presented in a simple form and for more details please view the models generated by Ramses and their corresponding action methods The parameters of the signals have been left out and these can be found in Appendix H These state machines are influenced by the test and demonstrator nature of the SCG system for this thesis It should be noted that some choice functionality of state machines has been handled by the action statements as to provide greater flexibility during implementation and testing In addition the amount of states presented is in some cases fewer than would be natural for an actual implementation This is to reduce the possibilities for input inconsistency to focus on application functionality and services The state machines may also be seen in the model view provided by Ramses a SCSAgent Here the state machines of the inner actors of the SCSAgent are presented SCSRouter The ports used by the SCSRouter are ScsrToScsca which is connected to the SCSControlAgent and ScsrToOsapia which is connected to the OSAPIAgent The variables mySCSS and 55 are ActorAddresses for the
64. upon sensor data deviations sea cage out of position Furthermore the demonstrator can detect a failed communication link and switch to the backup GPRS modem generate alarms and continue to provide basic services All elements and their status are reported and registered in a database and are presented through a dynamic web interface The demonstrator has shown that ActorFrame can be utilized to provide the necessary functionality the SCG domain requires A few improvements are proposed for the framework to increase the flexibility and performance of the system especially in the area of handling the distribution of actors on independent nodes and how the heterogeneous network technologies present in SCG system require a higher level of network awareness on behalf of the application This thesis has also suggested several possible extensions and future areas of work 5 SCG A Distributed Sensor Management Network in ActorFrame SCG A Distributed Sensor Management Network in ActorFrame Preface This master thesis has been written for the Norwegian University of Science and Technology Department of Telematics in the period March 2006 to August 2006 The basis for this thesis is the Sea Cage Gateway project This project aims to examine the possibilities of wireless remote sensor administration of fish sea cages These cages are to be placed further offshore than current practice is thus creating new demands on surv
65. 0 A high level communication diagram for issuing position deviation alerts If wished for the SCS could issue subsequent position alerts in pre determined intervals to allow for constant SMS updates of the latest position to rescue teams attempting to locate and salvage the fish cage This has not been implemented in this system and only one SMS warning is sent The updated position however 15 still reported in to the MS and is available from the database 8 4 8 Ensuring the detection of failures and appropriate actions As described in section 8 2 4 there are several modes of communication link failure that the SCG system must detect and handle The system has been designed so that all communication traversing communication links 15 either handled by the respective Router actors or by the respective Session actors This reduces the number of interacting actors over distributed links and makes it easier to detect and handle link failures When a message is sent from a Session actor or a Router actor a timer is set by the entity which makes a request All requests require a response within a pre defined time interval Upon a timer trigger the sending entity can either resend the signal or take other appropriate actions This could either be initiating the reserve communication link or issuing an alarm about a broken communication link depending on which side of the collaboration the actor is 78 SCG A Distributed Sensor Manage
66. 9 3 The SCS node computer All machines have been installed with Eclipse 3 1 2 Ramses 2 0 0 M9003 plug in tool and ActorFrame 2 0 4 The ActorFrame standalone support described in section 7 2 2 2 has been used for running the agents 9 1 2 The GPS receiver In this SCG system only one type of sensor is used and this is a GPS receiver connected to the SCS node computer The GPS sensor used is a Haicom HI 204III GPS receiver 51 and is shown in Figure 9 4 http www ubuntu org 9 SCG A Distributed Sensor Management Network in ActorFrame Figure 9 4 The Haicom GPS receiver The GPS receiver outputs NMEA 52 messages which require parsing to be accessible for other entities The NMEA output format is defined by the National Marine Electronics Association and the formats supported by the GPS receiver are shown in Table 9 1 Table 9 1 NMEA messages supported by the GPS receiver NMEA message Description GCA Global Positioning System Fix Data GLL Geographic Position Latitude Longitude GSA GNSS DOP and Active Satellites GSC GNSS Satellites in View RMC Recommended Minimum Specific GNSS Data VTG Course Over Ground and Ground Speed All of these messages provide some unique information whilst some information is present in several messages such as longitude and latitude An example of a received message is SGPGGA lt 1 gt lt 2 gt lt 3 gt lt 4 gt lt 5 gt lt
67. ARDINALITY AND 8 22 2 22 2 00000000000010100000000000000 00000 40 RE 8 3 HOW THE SCG SYSTEM IS CREATED 4 404020 002 0024 000000000 41 RE 8 4 PRELIMINARY ILLUSTRATION OF MOBILE APPLICATION INTERFACE 42 RE 8 5 THE SCG SYSTEM ELEMENTS NODES AND DEPLOYED 8 45 8 6 THE SCS ENVIRONMENT sos teer O tee en 46 6 7 THE CS ENVIRONMENT eoe seeds octane 48 9 8 ug eee Rove Eee esee a 49 RE 8 9 THE COMMUNICATION SCHEMES OF THE 51 RE 8 10 A SEQUENCE DIAGRAM SHOWING FAILURE OF DIFFERENT COMMUNICATION LINKS 52 RE 8 11 THE SCSAGENT ACTOR DESIGN cccssscccesssececsesceceessececseseececeeeeeeessaeeecseseeeseseeecseaeeeceeaaess RE 8 12 THE OSAPIAGENT ACTOR DESIGN eee RE 8 13 THE SENSORMANAGER ACTOR RE 8 14 THE GPSSENSORAGENT ACTOR DESIGN RE 8 15 THE CSAGENT ACTOR DESIGN ccccsessecesssececseseecessececsssaececseeeceesuececseseeseeseeecseaeeeeseaaees RE 8 16 THE SCSMANAGER ACTOR DESIGN eere etre nene rns RE 8 17 THE MSAGENT ACTOR 6 20 2 0000020001000000000000010000000000 RE 8 18 THE CSMANAGER ACTO
68. As there is only one SCS node using the ECS in the demonstrator system the CSSession can handle the communication for this SCS and the ReserveSCSSession actor has not been implemented GroupManager actor To handle the two essential group s defined in 1 maintenance and rescue these have been assigned to the GroupManager actor This is shown in Figure 8 20 61 5 SCG A Distributed Sensor Management Network in ActorFrame GroupManager lt lt Actor gt gt 1 1 ServiceGroup RescueGroup Figure 8 20 The GroupManager actor design These have not been implemented in the system as their functions have not been completely determined MSControlAgent actor This actor is similar to the control agents introduced in the SCSAgent and CSAgent This actor controls MS necessary operations With further research into the workings and desired functions of the MS node this actor s functions may be distributed to other actors or it may not be necessary at all DBEdge actor The DBEdge actor registers collected sensor data and other information in a database for storage and later retrieval SMSEdge actor The SMSEdge provides an edge to an SMS server for enabling possibility of for instance generating alarms to rescue groups or providing status information The possibility of handling incoming SMS to retrieve information or adjust settings could also be implemented WAPEdge actor The WAPEd
69. CS node for handling Sending the data as an object such as the ones described enables easy handling for the CS node Sending it simply as a String may result in information loss Since ActorFrame probably does not support the serialization of foreign objects the transport of these can at least for the time being be tricky Alternatives are representing information in ordered Strings or using XML requiring the recipient to use parsers to recreate the objects Other issues include bandwidth requirements of the different alternatives Further work on the grid computing mobile grid concept of the SCG system is also an interesting area of possible research In the demonstrator the presence and addresses of all nodes are propagated through the system when an element is added This knowledge of system entities has not yet been utilized to provide further services There are many possible application areas of such an extension amongst others task sharing and resource handling Such services could further improve the autonomy of the SCG system by extending redundancy self healing and self configuring abilities When sensors nodes or links go down the system entities can work together in reassigning the work loads taking turns to perform tasks to lengthen battery life time without reducing the amount of work done The tasks usually handled by the CSAgent 120 SCG A Distributed Sensor Management Network in ActorFrame can be redistribut
70. CSRouter The application initiates the GPRS connection Telenor GPRS through system commands executed by the Runtime object The command for initiating the pre defined dial up connection called Telenor GPRS is This command initiates and connects the GPRS modem to the service provider and alerts that the connection 15 up and running This is shown in a screenshot presented in Figure 9 8 4 Telenor GPRS is now connected x Speed 115 2 Kbps 24 Figure 9 8 Telenor GPRS has been initiated For disconnecting the connection the following command is used 97 SCG A Distributed Sensor Management Network in ActorFrame 9 2 3 DBEdge DBEdge actor has been implemented to show how ActorFrame can interact with databases It also shows the flexibility achieved through the use of a database in this system not only for registering sensor data but also for registering system elements such as CS nodes and SCS nodes and their current status In addition database interaction support is available for many languages and provides several options for the display manipulation and insertion of information The database designed and implemented here is a very simple relational database created purely for the demonstrational purposes of this simulator A far more detailed database design is discussed and presented in 2 The design for the database used in this system is shown in Figure 9 9 MSName Statu
71. CSSession of the CSAgent updating the database status and alerting the proper personnel to ensure swift repairs 80 SCG A Distributed Sensor Management Network in ActorFrame The messages exchanged between the distributed actors are also shown in the communication diagram presented in Figure 8 42 comm SCS detects PCS failure 3 J Database SMS Server 1 2 ChangeSCSCommLink 1 3 AlertPCSDown MSAgent 1 1 SCSPCSFailed 1 4 SCSPCSDown lt SCSAgent CSAgent 1 InitECS Figure 8 42 A high level communication diagram for when a PCS fails In the implementation the CSSession actor handles all SCS nodes under their CS node when the PCS is down As suggested in section 8 2 3 a ReserveSCSSession could be initiated to handle each SCS in ECS status The other possible scenario the case of a detected failure from the CS side of the collaboration is handled somewhat differently The sequence diagram for this is shown in Figure 8 43 SCG A Distributed Sensor Management Network in ActorFrame sd PCS failure detected by CS csca CSControlAgent scss SCSSession scsr SCSRouter csr CSRouter css CSSession GetSensorUpdate T gt GetSensorUpdate T 1 1 1 1 1 1 1 1 1 1 SET NOW time connectionTimer 1 1 1
72. ControlAgent actor forwards the sensor data received to the CSDataAgent actor for storage A communication diagram showing the interactions between the distributed actors is shown in Figure 8 34 To all SCSAgents in turn 1 GetSensorUpdate comm CS requests a sensor update lt SCSAgent CSAgent 1 1 SCSSensorDataUpdate 22 Figure 8 34 A high level communication diagram for sensor data retrieval from SCS nodes This pattern is identical to the one used between the MSAgent and its CSAgents except there is no update to an external database here This could be implemented at a later stage if necessary 8 4 2 3 Communication between SCS and sensors A major part of this system is the acquisition distribution and utilization of sensor data retrieved from the sensors installed at each SCS node A general sequence diagram for SCS sensor interaction is shown in Figure 8 35 This sequence diagram is identical for sensors attached to CS node 74 SCG A Distributed Sensor Management Network in ActorFrame sd SCS updating sensor data j SET NOW time SensorUpdateTimer scsda SCSDataAgent scsca SCSControlAgent sm SensorManager sca SensorControlAgent sda SensorDataAgent T T T T T 1 1 1 1 1 SensorUpdateTimer GetSensorUpdate gt
73. E 9 1 THE MS NODE COMPUTER csssssccccccscsssscecececsesssseaececcesesenseaecececseseuaeeeeececsessaaeeeeeceesensaaees FIGURE 9 2 THE CS NODE COMPUTER FIGURE 9 3 THE SCS NODE COMPUTER FIGURE 9 4 THE HAICOM GPS RECEIVER ccccsesssscecececeessnsececececsessnseaececccsesesaaecececsesersaaeeeeeceesensaaees FIGURE 9 5 THE TELTONIKA GPRS MODEDM cccssssccececeesesscececececsenseaececececsesseaeceeccsesenseaeceeeceesensaaees FIGURE 9 6 THE CLASS DIAGRAM FOR LOGGINGSERVER FIGURE 9 7 THE CLASS DIAGRAM FOR GPSHANDLER FIGURE 9 8 TELENOR GPRS HAS BEEN INITIATED esee nnns FIGURE 9 9 THE SCG DATABASE DESIGN 2 0 2 2 1 0 00000000000000000000000000100000000000 eren nenas FIGURE 9 10 THE CLASS DIAGRAM FOR THE DBEDGESM FIGURE 9 11 THE CLASS DIAGRAM FOR 5 2 0 040000000 FIGURE 9 12 THE SMS WARNINGS GENERATED FOR GPS POSITION DEVIATION LEFT AND LINK FAILURE RIGHT io as debit tee e get uet FIGURE 9 13 THE ADMINGUL ccccsssscsnceccceceenscscecccscessenecnsccscessensccecesscsceensceeeeseescessseeneeesesceessenee FIGURE 9 14 THE ASSIGNMENT OF THE DEFAULT GATEWAY OF ACTORROUTER FIGURE 9 15 A SCREENSHOT OF THE SCG SYSTEM WEB INTERFACE eene enne FIGURE 9 16 THE SCS STATUS HAS BEEN SET TO YELLOW FIGURE 9 17 THE SCS STATUS HAS BEEN SE
74. G system and represents the SCG system to the environment through a variety of interfaces The operating environment of the MS node is shown in Figure 8 8 Administration e Maintenance team e Rescue team Database Webserver Figure 8 8 The MS environment As seen in the figure the environment of the MS node represents many external entities and participants This is the main area of interaction for the SCG system The elements present in the environment of the MS node are described in Table 8 6 Table 8 6 MS node environment descriptions Environment Description element CS node The CS node represents a collection of sea cages and provides the data retrieved from these as well as forwarding commands for the MS node SCS node Under the failure of some of the communication links the SCS node will interact directly with the MS node Database information retrieved from all the sea cages must be systemized and stored in a database for later retrieval and use MCS Although the MS node cannot handle any failure in a 49 A Distributed Sensor Management Network in ActorFrame communication link it must be aware of it so it can alert maintenance teams Web server Providing information to a web server for easy access will greatly increase the accessibility to the system Administration Access to systems settings such as for instance changing the repo
75. IVATE Fisheries Aquaculture Shipping Figure 2 5 The SeaWatch system overview 9 SeaWatch is an international marine surveillance and warning system and collects both oceanographic and metrological data The concept of sensor data and networks connected to autonomous systems with self contained power supplies provides many SCG A Distributed Sensor Management Network in ActorFrame of the same basic functions that the SCG system will need and include The system uses satellite communication for its remote operations whilst utilizing cable and telephone lines for communication with fixed locations installations An application area for the SCG system is the detection of drifting cages via GPS Projects aiming at remotely determining fish cage positions and identifying drifting cages have been conducted An example is the use of Radarsat F5 radar images for detecting and positioning fish cages 10 As an alternative to satellite imagery radar images are not hampered by bad weather or cloudy conditions The radar images used are shown in Figure 2 6 200 m m 10 Although results of this project concluded that this technique did allow for detection and positioning of fish cages it is a somewhat extensive process This can probably easily be replaced by installing GPS recivers with adequate monitoring systems on sea cages as part of the SCG system SCG A Distributed
76. N OF THE 6 8 4 424 4 01 40 0 4400 2000000000000000000005800 53 834 SCSA GEN ys caeteri e edes 54 8302 CSASCNE s etes ete eee detti ee ee 58 83 31 MS n iet RR 59 8 4 SEQUENCE AND COMMUNICATION 8 2 22 44 2 63 Setting Up the system dde 63 8 4 2 Communications for sensor data retrieval under normal 69 8 4 3 Ensuring the detection of failures and appropriate actions sss 78 8 4 4 Communications under ECS operation sss eee 86 IMPLEMENTATION AND DEPLOYMENT 4 4 4 0004000 90 9 1 potrete pel cleo ee iet unes 90 911 Node compl lers eee A Rescue 90 912 IheGPS recei ve 91 9 1 3 Reserve COMMUNICATION 93 9 2 IMPLEMENTED 94 9214 GPSSCNSOP ee eter orte ee tue 94 9 2 2 OSAPIAgent and WindowsAPIEdge eese 96 92 3 IDBEd9ex o o iom eun em eee UE 98 02247 SSM SHAG A eode eet qst dete tuvo RE erm ENT 99 9235 A dminEdge iere oe geo ber 100 926 ActorRouter setup tarnen re
77. NSOR NETWORK 17 entente rennen nnns enne 16 RE 4 5 THE GENERALIZED CONCEPT OF SENSOR WEB 21 esee 19 6 1 COVERAGE MAP FOR TELENOR GPRS 251 1 2 4 44 8 400000 000000000000 23 RE 6 2 COVERAGE MAP FOR 450 FOR THE PORTABLE BROADBAND MODEM 27 24 6 3 EXPECTED COVERAGE FOR TELENOR SEALINK 30 seen 26 RE 7 1 A CLASS IN UML2 0 WITH INTERNAL STRUCTURE PORTS AND CONNECTORS 42 29 RE 7 2 ERICSSON S DEVELOPMENT FRAMEWORK 42 RE 7 3 THE ACTOR CLASS 42 RE 7 4 THE ELEMENTS OF A PLAY 42 aie RE 7 5 THE ROLEREQUEST PROTOCOL 42 essere enne RE 7 6 DISTINGUISHING BETWEEN DELEGATION AND BEHAVIOUR PORTS eee 33 RE 7 7 THE ACTORFRAME MANAGEMENT nennen ener enne nennen enne nnns 34 RE 7 8 AN INFORMAL SEQUENCE DIAGRAM ILLUSTRATING ACTORROUTER PROTOCOL 35 RE 7 9 THE WORKINGS OF ACTORROUTER 2 2 2 00000 02000000000000000000050000000 nnn 36 7 10 THE APPLICATION DOMAIN INCORPORATED BY SERVICEFRAME 45 37 RE 7 11 THE RAMSES TOOL SUITE 47 enne nennen 38 RE 7 12 SCREENSHOT OF THE RAMSES MODEL VIEW IN ECLIPSE cese 38 RE 8 1 INTEROPERABILITY BETWEEN NODES MOBILE 40 RE 8 2 SYSTEM C
78. R DESIGN 2 2 0010100000000000000000000 RE 8 19 THE CSSESSION ACTOR sienten eterne RE 8 20 THE GROUPMANAGER ACTOR DESIGN ccce asserere nnn RE 8 21 THE INTERCOMMUNICATING ACTORS OF THE 8 RE 8 22 THE SEQUENCE DIAGRAM FOR A NEW CS REGISTERING WITH MS RE 8 23 HIGH LEVEL COMMUNICATION DIAGRAM FOR A NEW CS REGISTERING WITH MS 65 RE 8 24 THE SEQUENCE DIAGRAM FOR NEW SCS REGISTERING WITH 66 RE 8 25 A HIGH LEVEL COMMUNICATION DIAGRAM FOR A NEW SCS REGISTERING WITH CS 67 1 SCG A Distributed Sensor Management Network in ActorFrame FIGURE 8 26 THE SEQUENCE DIAGRAM FOR CONNECTING A NEW SENSOR A 68 FIGURE 8 27 A HIGH LEVEL COMMUNICATION DIAGRAM FOR A NEW SENSOR BEING CONNECTED TO A SOR UTE REPE EA 68 FIGURE 8 28 HOW SENSOR DATA IS RETRIEVED FROM THE NODES OF THE 5 5 8 70 FIGURE 8 29 THE SEQUENCE DIAGRAM FOR THE COLLECTION OF SENSOR DATA FROM THE MS NODE 71 FIGURE 8 30 A HIGH LEVEL COMMUNICATION DIAGRAM FOR SENSOR DATA RETRIEVAL FROM THE 5 NODES 5o eere oi dre e fe so e 72 FIGURE 8 31 THE SEQUENCE DIAGRAM FOR THE HANDLING SENSOR UPDATE REQUESTS BY THE CS 72 FIGURE 8 32 THE SEQUENCE DIAGRAM FOR A CS UPDATING ITS
79. Router returns to normal operation routing signals to SCSSession and issuing connection checks and maintaining the connection to the MSA gent OK OK SCSControlAgent returns to normal operation readjusts the timer interval and discontinues direct reporting to the CSSession OK OK d The database is updated with the new communication link and the status is set to green given no other alarms are active OK OK 140 SCG A Distributed Sensor Management Network in ActorFrame Appendix C In this chapter the implementation of the database used in the SCG system is presented Database setup a The database columns and types In Table C 1 the tables with their columns and column types are presented Table C 1 The scgdb database design scgdb Database Finalized Column name Table Column type msid MS SMALLINT 3 UNSIGNED NOT NULL statusid MS SMALLINT 3 UNSIGNED NOT NULL msname MS VARCHAR 30 NOT NULL SMALLINT 3 UNSIGNED NOT NULL csid CS AUTO INCREMENT msid CS SMALLINT 3 UNSIGNED NOT NULL statusid CS SMALLINT 3 UNSIGNED NOT NULL csname CS VARCHAR 100 NOT NULL SMALLINT 2 UNSIGNED NOT NULL scsid SCS AUTO INCREMENT SMALLINT 3 UNSIGNED NOT NULL csid SCS AUTO INCREMENT statusid SCS SMALLINT 3 UNSIGNED NOT NULL scsname SCS VARCHAR 100 NOT N
80. S between CS and MS Another scenario is that of the FCS failing If this happens the SCS node must be alerted so it can initiate ECS to preserve communication capabilities until the FCS and MCS are repaired or restored Under the assumption that the MCS between a CS and its MS has failed and that the FCS is currently in use the sequence diagram is shown in Figure 8 46 84 5 SCG A Distributed Sensor Management Network in ActorFrame sd FCS failure css CSSession csr CSRouter cscs CSControlAgent scsm SCSManager scss SCSSession scsr SCSRouter T T ConnectionCheck SET NOW time connectionTimer STOP connectionTimer T 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 connectionTimer 1 1 1 1 1 T 1 1 1 1 1 1 1 I J ConnectionCheck 1 e Ecs failure handling in SCS GPRSInit ed o 1 1 1 1 1 1 1 1 1 i 1 FCSDown FCSFailed 1 1 FCSFaled FCSFailed 1 1 1 L 1 1 1 1 1 1 1 1 L 1 1 1 1 1 Figure 8 46 The sequence diagram for FCS failure When the FCS fails the only means of communication remaining is the ECS When a FCS failure is detected the CSControlAgent actor alerts the SCSManager that the FCS is do
81. S nodes The SCSManager via the SCSSession actors continues to poll the SCS nodes for sensor data one at a time using scsList similar to the csList This is both to minimize the traffic and congestion on the PCS link reducing energy consumption but this also makes it easier to maintain the status of all link and collaborating parties The sequence diagram for this procedure is shown in Figure 8 33 sd The CS requests sensor data from its SCS csca CSControlAgent scsm SCSManager scss SCSSession scsr SCSRouter scsa SCSControlAgent scsda SCSDataAgent RetrieveSCSSensorUpdate 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 loop 1 scsList size 1 t 1 1 GetSensorUpdate i gt GetSensorUpdate 1 1 1 1 GetSensorUpdate 1 1 1 1 GetSensorUpdate 1 1 1 1 L gt 1 1 1 1 1 1 1 SCSSensorUpdate sensordata 1 1 1 SensorDataRetrieved sensorData 1 N 1 1 SensorDataRetrieved sensorData b i 1 l 1 1 1 1 Figure 8 33 The sequence diagram for retrieving sensor data from CS node s SCS nodes 73 SCG A Distributed Sensor Management Network in ActorFrame This procedure is similar to the one where the MSAgent retrieves the sensor data from its CSAgents The CS
82. SOME BASIC FUNCTIONAL REQUIREMENTS FOR THE SCG SYSTEM SOME NON FUNCTIONAL REQUIREMENTS enne ener rennen nennen rennen eren SCS NODE ENVIRONMENT DESCRIPTIONS ccessessssecececsesssssceecceceesesseceeececeesesssaeeeeececeensaaes SCS NODE TASKS t Ee EE UE Pe s etas tee CS NODE ENVIRONMENT DESCRIPTIONS MS NODE ENVIRONMENT DESCRIPTIONS THE MS NODE TASKS ein tarre i a a aeae ai e a e iaieiiea SCG SYSTEM FAILURE MODES AND CORRESPONDING ACTIONS NMEA MESSAGES SUPPORTED BY THE 8 THE DATA OF THE GCA MESSAGE 53 1 1 4 4 1 00011100000 000000000000 TEST RESULTS AGAINST FUNCTIONAL REQUIREMENTS SYSTEM PROJECTS WITH 8 2 0 000100000000 TEST OF THE SYSTEM SETUP FUNCTIONALITY ccce eene enne nennen nnne eene tenant TEST OF THE SENSOR UPDATE FUNCTIONALITY 0000000000000101000000000 TEST OF THE SENSOR DEVIATION AND PCS FAILURE DETECTION AND 138 TEST OF THE SENSOR REPORTING AND ALERT GENERATION IN ECS MODE THE SCGDB DATABASE DESIGN sssscccccccsessssssececececsesseaeeecececsessasececececsessaaeaecececsessaaeeeeees LIST OF SIGNALS IN THE 5 8 2 2 2 2000000000000000000 TABLE I 1 THE CONTENTS OF APPENDIX xi 5 SCG A Distributed Sensor Management Network in Acto
83. T TO RED AND ECS HAS BEEN FIGURE 9 18 THE DEMONSTRATOR SETUP ENVIRONMENT FIGURE 9 19 PICTURE OF THE TESTING FIGURE 9 20 THE SCGSYSTEM ACTOR DESIGN FIGURE 10 1 ALTERNATIVE COMMUNICATION 8 2 1 11000 FIGURE 10 2 ALTERNATIVE SCSAGENT DESIGN FIGURE 10 3 THE SCSINITIATOR ACTOR DESIGN FIGURE 10 4 POTENTIAL ACTORS IN AN EXTENDED SCG DOMAIN FIGURE 10 5 THE FORMER ENVIRONMENT FOR ACTORFRAME APPLICATIONS ee FIGURE 10 6 THE FUTURE ENVIRONEMNT FOR ACTORFRAME APPLICATION DEVELOPMENT SCG A Distributed Sensor Management Network in ActorFrame List of tables TABLE 3 1 TABLE 3 2 TABLE 4 1 TABLE 6 1 TABLE 8 1 TABLE 8 2 TABLE 8 3 TABLE 8 4 TABLE 8 5 TABLE 8 6 TABLE 8 7 TABLE 8 8 TABLE 9 1 TABLE 9 2 TABLE 9 3 TABLE 1 TABLE B 1 TABLE B 2 TABLE B 3 TABLE B 4 TABLE C 1 TABLE 1 THE ELEMENTS OF THE SEA CAGE GATEWAY SYSTEM nennen en ener nennen 9 THE PROPOSED COMMUNICATION LINKS OF THE SEA CAGE GATEWAY 11 INTERESTED PARTIES IN SENSOR DATA FROM THE SCQG SYSTEM 000 19 COMMUNICATION LINK CHARACTERISTICS AND AREAS OF 28
84. TIONS XIII 1 INTRODUCTION m E 1 1 1 E 1 1 2 SCOPE uc vetet eh 1 1 3 ASSUMPTIONS AND 8 8 00000000001000000000000002000000 2 1 4 PROJEGT OUTEINE ee Pe tpe Pee train Pee e to Ree 2 2 AQUACULTURE aee a aea aen eee ca 3 2 1 THEHISTORY OF AQUACULELTURE osea tecta e octo ete te e oue ua e TU Se cb kd te cod 3 2 2 FACTORS AFFECTING AQUACULTURE 3 2 3 CAGE TECHNIQUES e IR vet te Ee OO EE E UOTE 4 2 4 AQUACULTURE IN THE FUTURE e terea een eee Ro TU TRE 6 2295 NEW DEMANDS FROM MARKETS cssssscccccecsesssececececeessaececececsessnaeceeececeessaaeeeeececsensaeeeteceesenes 7 2 6 CURRENT RELATED TECHNOLOGY USED IN AQUACULTURE AND AQUATIC ENVIRONMENTS 7 3 THE SEA CAGE GATEWAY PROJECT 9 3 1 DOMAIN DESCRIPTION E 9 no mme m Ut 11 3 2 PREVIOUS WORK ON THE 13 4 SENSORS 14 4 1 SENSOR TYPES M
85. There was also a problem with signal parameters being sent over distributed links When the parameter was of the type ActorAddress the content was null after being transmitted But if the method getSenderRole was applied on the received signal the ActorAddress here was still valid It was eventually discovered that Ramses does not seem to support the serialization of ActorAddresses which are contained as parameters in ActorMessages ActorFrame however does support this and this is why the getSenderRole method still worked The additional code necessary was discovered by examining the framework Thus to allow for the serializaiton of ActorAddresses in ActorFrame the following line of code must be included in the serialize method of the generated signal class from Ramses dout write ActorAddressHelper persist actoraddress In the deserialize method of the generated signal class the following line of code must also be included actoraddress ActorAddressHelper resurrect actoraddress It was then subsequently added manually to all signals generated by Ramses that were to be sent over communication links and contained ActorAddresses as parameters ActorFrame also generates inconsistencies in its way of addressing actors when distributed Two methods often used to identify Actor addresses are getMyActorAddress on ActorSM s and getSenderRole on ActorMsg s A typical address received from the first method is
86. ULL SMALLINT 3 UNSIGNED NOT NULL statusid Status AUTO INCREMENT statusname Status VARCHAR 30 NOT NULL SMALLINT 3 UNSIGNED NOT NULL sensorid Sensor AUTO INCREMENT sensortypeid Sensor SMALLINT 3 UNSIGNED NOT NULL csid Sensor SMALLINT 3 UNSIGNED scsid Sensor SMALLINT 3 UNSIGNED sensorvalue Sensor VARCHAR 30 SMALLINT 3 UNSIGNED NOT NULL sensortypeid SensorType AUTO INCREMENT sensorname SensorType VARCHAR 30 NOT NULL SMALLINT 1 UNSIGNED NOT NULL commlinkid CommLink AUTO INCREMENT commlinkname CommLink VARCHAR 30 NOT NULL 141 SCG A Distributed Sensor Management Network in ActorFrame b Database query sentences In this section the SQL sentences used to initiate the tables of the scgdb database are described The sentences presented were run in the mySQL client window To create the database To create a user with read and write permissions from localhost This creates a user called user with all privileges on the scgdb database with the password This is used to access the database from the SOLInterface class and the scgstatus jsp web interface Giving all privileges to a user is under normal circumstances not a good idea but for a demonstration it makes access and interaction much easier This user is the one used by the SOLInterface class in Appendix D and the scgstatus jsp class in Appendix E To create the ms table To create the cs table To create
87. URL http www akvasmart no products getProductData ASP productid 174 amp drop ID 20 amp productlist 20 AkvaSensor Biomass Estimator viewed 29 05 2006 URL http www akvasmart no products getProductData ASP productid 150 amp drop ID 20 amp productlist 20 AkvaSensor Oxygen viewed 29 05 2006 URL http www akvasmart no products getProductData ASP productid 150 amp drop ID 20 amp productlist 20 Wikipedia Sensor Networks viewed 19 04 2006 URL http en wikipedia org wiki Sensor Networks Sensor network illustration retrieved from URL http www dei unipd it schenato pics SensorNetwork jpg A Manjeshwar Q Zeng D P Agrawal An Analytical Model for Information Retreieval in Wireless Sensor Networks Using Enhanced APTEEN Protocol JEEE Transactions on Parallel and Distributed Systems v 13 n 12 December 2002 p 1290 1302 M AboElFotoh S S Iyengar K Chakrabarty Computing Reliability and Message Delay for Cooperative Wireless Distributed Sensor Networks Subject to Random Failures JEEE Transactions on Reliability v 54 1 March 2005 p 145 155 K A Delin The Sensor Web A Macro Instrument for Coordinated Sensing Sensors 2002 2 270 285 URL http www mdpi net sensors papers s20700270 pdf Delin The Sensor Web A Distributed Wireless Monitoring System Sensors Online 2004 viewed 4 7 2006 URL http www sensorsmag com articles 0404 20 Grid Computin
88. a new IP address from the connection This must also be considered especially with the application level routing used by the ActorFrame ActorRouter The actions taken upon link failure are summarized in Table 8 8 Table 8 8 SCG system failure modes and corresponding actions Failure Actions PCS detected ECS is initiated and the CS node and MS node are notified The CS by SCS node is notified through the MS node Alarms are generated 52 SCG A Distributed Sensor Management Network in ActorFrame PCS detected The MS node is notified and alarms are generated by CS MCS detected Alarms are generated by MS MCS detected FCS is initiated and the MS node is notified by CS FCS detected Alarms are generated by MS FCS detected The SCS is notified and ECS is initiated SCS then notifies the MS by CS and alarms are generated Nodes A node failure will manifest as a communication link failure and be detected through the same routines with some few additions When all communication schemes fail the sea cage constellation is completely isolated The rest of the system will detect this and the correct actions will be taken The sea cages could upon failure of all communications take turns in a round robin style registering sensor data and testing communication links When systems are restored the rest of the SCS nodes return to a normal operating modus again Such functiona
89. able from Appendix I 7 Install the GPS receiver Ensure that this is connected to 12 8 Initiate the GPRS modem 9 Run the simulation by right clicking on default package in the simulation project Select Run AS gt Java Application 10 11 The ActorFrame management console should appear Select RoleRequestMsg from the drop down menu specify the recipient as actor type SCGSystem actor id scgs First a request CSAgent by setting the first parameter as csa and the second parameter as CSAgent 134 SCG A Distributed Sensor Management Network in ActorFrame 12 Repeat the same steps only use scsa and SCSAgent as parameters to request a SCSAgent 13 The simulation should now be up and running By moving the GPS receiver an alarm should be generated By altering the code of the SCSSession actor responses to the connectionCheck signal can be disengaged and the PCS link is assumed down 14 The status of the system can be viewed at the address of the web server Assuming that the port has been set to 8080 the address is http localhost 8080 scgstatus jsp For testing the distributed system the projects scsagent csagent and msagent must be imported to their respective nodes The GPS receiver and the GPRS modem must be installed and setup on the SCS node The public addresses and default gateways of the actors must be specifed in the AF Properties properties file
90. addition to sensor web functionality will inevitably provide many challenges in establishing the ideal non functional requirements Amongst non functional requirements of the SCG system demonstrator to be designed and implemented a few are displayed in Table 8 2 Table 8 2 Some non functional requirements Non functional Description requirement Sensor update How often should sensor readings be performed This will interval probably vary from sensortype to sensortype and in different scenarios If the SCS node begins drifting a higher frequency for polling the GPS receiver could be necessary SCS status update How often should the status and sensor reports be collected interval from the SCS CS status update How often should the status and sensor reports be collected interval from the CS PCS latency What is the maximum round trip delay allowed for the PCS maximum link MCS latency What is the maximum round trip delay allowed for the MCS maximum link PCS status check How long should it take between checking the PCS status interval What is the maximum time window given before a reply is required This is again dependent on the link latency MCS status check How long should it take between checking the MCS status interval What is the maximum time window given before a reply is required This is again dependent on the link latency GPS deviation How far should a position be from a pre defined are bef
91. al in addition to the administration rescue teams or other interested parties The terminals are the node hardware and operating systems and user introduced elements PDA laptop smart phone The nodes with sensors can be seen as service providers service enablers and service cutsomers These are some possible suggestions for modelling the SCG system in ServiceFrame 7 2 4 MidletFrame MidletFrame is a stripped down version of ActorFrame implemented in J2ME This opens for using ActorFrame concepts on small mobile devices and allows interaction with standard ActorFrame actors MidletFrame incorporated on smart phones could be used for mobile terminals interacting with nodes on site These can incorporate Bluetooth for service discovery and node presence This allows for the smart phone to directly and seamlessly interact with the ActorFrame elements already present 7 3 Ramses Ramses is a system development tool created at the Department of Telematics at NTNU It consists of a series of plug ins for the Eclipse platform 46 Ramses offers model editors code generators model checks and runtime trace support The tool is based on the UML2 0 specification as shown in Figure 7 11 37 SCG A Distributed Sensor Management Network in ActorFrame Figure 7 11 The Ramses tool suite 47 The editor allows for the design of the system using the elements from UML2 0 The inspectors provide means to check and validate the des
92. al tests have yielded ranges of up to and over several kilometres by using more advanced antennas The cost of such equipment is of course higher but this can then be utilized as the MCS as well WLAN is the suggested MCS and PCS of 1 As an MCS WLAN will quickly become the restricting factor for how far offshore the sea cages can be placed 6 4 Satellite communication Satellite communication is available throughout the world providing connectivity at any given location Telenor Satellite 29 provides a satellite service at sea called SeaLink 30 This technology can provide always on internet connectivity and coverage is shown in Figure 6 3 25 SCG A Distributed Sensor Management Network in ActorFrame AOR E IOR East Herni Hemi POR AOR IOR POR Global Beam Global Beam Global Beam Global Beam Figure 6 3 Expected coverage for Telenor Sealink 30 The SeaLink service offers data rates from 64 kb s to 8 Mb s 31 Issues such as power consumption and cost are difficult to estimate but the range provided by satellite communication is unmatched For a SCG system incorporating such a communication technology sea cages can be placed almost anywhere in the world It can function as both a narrowband and broadband technology for the SCG system and in a global perspective it is independent of the local communication infrastructure 6 5 VHF Data VHF Data uses released frequencies
93. al actors to handle these and send them As mentioned previously in section 8 4 2 2 using a generic signal for transporting sensor data in primitive types could be a way around this Such dynamic class configuration and its repercussions are both areas for future study As seen in this thesis when a node can have several network connections it is important for the application to be aware of this The previous environment for service development consisted of relatively similar nodes connected via a relatively standard network interface This environment for an ActorFrame application between two distributed entities is shown in Figure 10 5 122 SCG A Distributed Sensor Management Network in ActorFrame ActorFrame ActorFrame application application Operating Operating system system Hardware Network Network Hardware Figure 10 5 The former environment for ActorFrame applications Providing network transparency both in the traditional end to end transparency of the internet but also the separation of the application from the network layer is growing increasingly more difficult Not only must an application be aware of its own status hardware and network capabilities it must also consider the other collaborating actors capabilities The potential is limited by the weakest link The new and future environment for both ActorFrame and other development frameworks will be similar to that shown in Figure 10 6 Acto
94. alled on the computer that tested the simulated system d Testing communication between SCS and MS under ECS In this test the reporting and alert generating functions whilst the SCS node used the ECS link were tested This corresponds to functional requirement three The results are shown in Table B 4 Table B 4 Test of the sensor reporting and alert generation in ECS mode Function tested Expected behaviour Result Simulated Distributed 139 SCG A Distributed Sensor Management Network in ActorFrame Periodic messages with position updates are sent to CSSession a The CSControlAgent readjusts its sensor update timers in this new status OK OK b The GPSSensor Update message is sent to the CSSession by SCSRouter OK OK The GPS receiver is moved out of bounds The PCS is restored a The GPSControlAgent detects the threshold breach and immediately sends a PositionAlert signal OK OK b The SCSRouter sends the PositionAlert signal to CSSession OK OK c The CSSession 1s notified and in turn generates alarms and notifies the MSControlAgent OK OK d An alarm is issued by the SMSEdge OK OK The database is updated with position deviation The PCSRestored signal is received by the SCSRouter and forwarded to SCSControlA gent OK OK OK OK b SCS
95. and sensors specifically designed for the purpose A large actor in the fish farm technology market is AKVAsmart 8 They offer monitoring and data analysis equipment in addition to the sensors themselves These systems are proprietary and do not incorporate wireless technologies for long distance remote control and administration of fish farms AKV Asmart are involved with the SCG project with the intent to incorporate such technology into their current product portfolio Another system using many of the same components is the SeaWatch system 9 The SeaWatch system incorporates many similar functions only their focus is more on marine conditions in general rather than a sea cage specific application area A system overview is shown in Figure 2 5 OTHER DATA SOURCES SATELLITE Y gt m 2 1 REALTIME DATA i NK TRANSMISSION SATELLITE DATA WEATHER i FORECASTS 4 7 READDOWN UN amp STATION RESEARCH VESSE 5 COASTAL STATIONS o INFORMATION e DISTRIBUTION OCEANOGRAPHIC BUGYS PROCESSING CENTRE users SENSORS FOR METEOROLOGY AND WAVES CURRENT TEMPERATURE SALINITY OXYGEN ALGAE NUTRIENTS RADIOACTIVITY HYDROCARBONS CHLOROPHYLL NUM CAL MODELLING FORECASTING Coastguard Research institutions PUBLIC AND PRIVATE Resource management Metocean tenidas Ciffshare Recreation andl tourism PR
96. anding of virtual organizations extending to more recent scenarios with dynamic and undefined organizations with constantly varying access points This is a very recent area of research and an interesting one as such Finally two issues should be mentioned One is considering the amount of functionality necessary to provide the services required by the SCG domain Whilst grid computing and mobile environment adaptation may provide a great number of services and possiblilites they may introduce more complexity than is needed From a research point of view the SCG domain presents numerous possibilities within these fields all of which can probably enhance the SCG system but careful consideration should be taken as to when enough is enough The other issue is that technology today is improving at a fantastic rate both within computers and communication technologies Although one should not take for granted that this kind of development will continue there are currently no signs of it slowing down This should be taken into account and kept in mind when developing a system for the future a system such as the SCG system 124 SCG A Distributed Sensor Management Network in ActorFrame 11 Conclusion This thesis has investigated the use of distributed inter communicating state machines designed and applied with the play analogy of ActorFrame to the SCG domain This domain consists of interconnected independent computers interacting t
97. as of interest are listed in Table 4 1 3 Table 4 1 Interested parties in sensor data from the SCG system Party Area of interest Public authorities Authorities could follow up on legal restrictions and laws on fish food production and quality Consumers Consumers who are ecologically aware could be interested in 19 5 SCG A Distributed Sensor Management Network in ActorFrame tracking their fish product to its origin and receive data on the conditions experience by their product Aquaculture The aquaculture industry in general could collect and utilize sensor data for research and development Commercial fishing Could utilize sensor data on conditions in the offshore ocean areas Tourist industry Weather conditions Research institutes Oceanographic studies Navy coastguard Enforcement security rescues Offshore industr Safety Ship traffic Safety Constant updates to onboard GPS map with the current position of sea cages or generating drifting sea cage alerts could help avoid accidents The sensor data collected could be made available to many institutions listed in the table above and provides a valuable basis for research and testing in addition to administrating and optimizing the fish farm production As an example the onboard GPS map systems of large vessels can be automatically updated on the presence of new sea cages in addition to the position
98. at the operating system would prioritize the LAN connection whilst active Unfortunately it soon became clear that this would not work The reason for this was that the GPRS connection uses a PPP protocol This protocol requires the specification of a default gateway for all traffic overriding the metrics implemented in the routing table Due to this factor an OSAPIEdge actor was introduced to provide the administration of the GPRS link Another network issue uncovered during testing was the default private address allocation upon a GPRS connection This was solved by specifically requesting a public address through an alternative APN from the service provider It should be noted that although the GPRS connection handled all outbound traffic from the SCS node the node can still receive data on both active connection addresses LAN and GPRS when they both are operational This fact was used to restore the SCS to normal modus after a PCS failure had been resolved Even after the GPRS connection had received a public address messages originating from the SCS node were not received by the MS node At first it was thought that the GPRS modem did not support the serialization method of ActorFrame but the SCS node was able to receive signals without problems Finally it was revealed that the local firewall does not allow any traffic originating from the outside in to the local network Ports in the firewall were then opened for the MS node IP address
99. ateSCSCapabiliiesi p RegisterMS PosAlertForSCs gt PCSDown ew via pdate apabiltie ScsmToCsr via ScsmToCsr SCSSetupParameters pollingSCS SCSList ensorData via 2 PosAlertFor PCSDown ScsmToCsr false UpdateFinished vi ScsmToCsr GetSensorUpdate pollingSCS GetSensorUpdate pollingSCS 165 SCG A Distributed Sensor Management Network in ActorFrame SCSSession The variables mySCS and mySCSM are ActorAddresses for the SCSSession 5 SCS node SCSRouter and SCSManager SSCSPCSDown gt SCSList gt NewSensor wn Ist etupParameters Update mySCSM Soins SCSList TO mySC TO mySCSM updateSCSList idle SCSList Registered TS gt PCSRestored GetSensorUpdate mySCS ahs PCSDown pcsDown gt gt GetSensorUpdater GPSSensorData BeSConnectionCheck gt PositionAlert Ep d mySCS mySCSM TO mySCS mySCSM c MSAgent Here the state machines of the inner actors of the MSAgent are presented MSRouter The port MsrToCsm is connected to the CSManager the port MsrToDbe is connected to the DBEdge and the port MsrToSmse is connected to SMSEdge actor 166 SCG A D
100. available through aquaculture are many 2 1 The history of aquaculture The history of aquaculture goes back at least 4000 years 3 Unlike agriculture which has been the main source of food for generations and partially held responsible for the appearance of civilization aquaculture has contributed far less to the overall food consume Although the principle of rearing and harvesting fish and other aquatic food sources have been available for a considerable time the industry has been more concerned with improving classic hunter gatherer techniques to obtain food from the oceans Reasons for why agriculture and aquaculture took such different paths are mentioned in 3 among those is the apparent abundance of aquatic food combined with lacking knowledge of a foreign environment such as the marine one Recently the world demand for fish has superseded the amount available through traditional capture fishery After experiencing a steadily growing demand after World War II the production peeked in 2000 at 95 million tonnes 3 Despite this the available amount of fish not inluding the production in China has not changed much since the mid 1980s This gap has to be covered through aquaculture fisheries and a prognosis yields that fish production will equal or surpass traditional captures fishery production within the first quarter of the 21 century 3 In addition to responding to increasing demands for fish fish production also offers
101. calities allowing them to focus fully on service functionality 42 As is shown in the figure ActorFrame is based on JavaFrame and provides support for the higher levels of abstraction of ServiceFrame 30 SCG A Distributed Sensor Management Network in ActorFrame The frameworks build on concepts familiar from telecom domains with terminals and users wishing to communicate with each other In such a sense the SCG system is slightly different but that does not mean that it cannot provide modelling concepts for this domain 7 2 1 JavaFrame provides a framework implementing UML2 0 concepts such as state machines and composites in Java It also offers asynchronous message passing in Java By providing predefined classes for UML2 0 design concepts a model can be directly implemented using Java It also supports asynchronous messaging mechanisms such as identifying the sender of signals and applies the save concept known from SDL By using an underlying Scheduler JavaFrame simulates concurrency of Active objects It should be noted that the state machines of JavaFrame can only trigger transitions through the reception of signals this includes timers and does not support triggers such as changed values or method calls 42 The main classes provided in JavaFrame are StateMachine Composite and Mediators For more information about JavaFrame see 43 and 44 7 2 2 ActorFrame ActorF
102. cation diagram for this collaboration is shown in Figure 8 27 comm A new sensor is connected to a SCS 1 4 RoleRequestMsg 1 Database Sensor 2 Polling E NewSensor 2 3 AddSensorToDB 2 1 NewSensor 2 2 UpdateSCSCapabilites SCSAgent CSAgent MSAgent Figure 8 27 A high level communication diagram for a new sensor being connected to a SCS 68 SCG A Distributed Sensor Management Network in ActorFrame In this communication diagram the Sensor is presented as an actor outside the system This is not to be confused with the actor terminology used in ActorFrame The connection of a sensor generates an automatic RoleRequestMsg signal and the sensor is consequently queried The information of a new sensor is then propagated among the nodes of the SCG system and added to the database As shown in section 8 2 2 sensors may also be connected to the CSAgent actor This will be handled similarly as the sequence diagram except that it will be the CS capabilities that will be updated 8 4 2 Communications for sensor data retrieval under normal operation In the following section interaction between the different nodes under normal operating conditions are shown The interactions for this section have been limited to the acquisition of sensor data from lower level nodes There will be other forms of interacti
103. d latency requirements of the SCG system must be determined As the ECS satellite communication may be the best alternative due to the possible drifting of sea cages For MCS perhaps 450 is the preferred choice with FCS being VHF Data In time WiMax should be able to compete as being the primary choice for MCS 28 SCG A Distributed Sensor Management Network in ActorFrame 7 Framework and modelling concepts In this chapter the ActorFrame framework and adhering concepts are introduced UML2 0 is presented as this is the modelling language used by ActorFrame UML2 0 is also used for implementing the design into the Ramses tool suite also presented in this chapter 7 1 UML2 0 UML2 0 is the modelling language used for Ericsson Service Development Framework presented in the following sections UML is defined for object oriented development processes in 41 as The Unified Modelling Language UML is a general purpose visual modelling language that is used to specify visualize construct and document the artefacts of a software system UML2 0 is the continuance of UML and addresses the problems and shortcomings of the previous standard It also represents a convergence between computer and telecommunication architectural concepts Several of UML2 0 concepts are used for modelling ActorFrame based applications The most relevant elements are listed in 42 These are Parts Ports Connectors State Machine
104. d supply the necessary functions and classes a simple GPSHandler class has been written The GPSEdgeSM class creates a GPSHandler class upon initiation and this class then provides all the methods necessary for retrieving GPS data from the receiver The class diagram for the GPSHandler is shown in Figure 9 7 GPSInfo latitude double longitude double LatLng latitude double longitude double distance in lating LatLng double GPSHandler gpsUpdate in data string retrieveGPSPosition parse in s String in gpsi GPSInfo LoggingServer GPSSensorEdgeSM gpsh GPSHandler Figure 9 7 The class diagram for GPSHandler initiate The NMEA class of the JavaGPS package provides a parse method which parses NMEA messages and stores the results in a GPSInfo class As mentioned in section 9 1 2 there are several types of NMEA messages all containing different information To obtain the latitude and longitude only one type of NMEA message V http www gnu org licenses gpl html 95 SCG A Distributed Sensor Management Network in ActorFrame would be necessary However it could be interesting to access more of the data retrieved from the GPS receiver at a later occasion and therefore all messages are parsed The GPS nfo class contains more attributes then listed in figure but for this system only latitude and lon
105. d to such as scheduling and software and consistency management but this is beyond the scope of this thesis 21 SCG A Distributed Sensor Management Network in ActorFrame 5 1 Mobile Grid Since the introduction of grid computing the network technology has been constantly changing and improving This has lead to two major changes The first is the dimension of mobility introduced by wireless communication the other is the abundance of heterogeneous communication links Furthermore the introduction of small handheld devices such as the PDA and the smart phone represent terminals which can really appreciate the services of grid computing Previously the environments for grid computing were considered relatively homogenous stable and centralized to a certain degree 24 Now even a low end mobile phone provides at least GSM and GPRS often Bluetooth and IrDA and increasingly more common 3G and WLAN With the advent of these new technologies the extended grid the mobile grid poses many challenges The wireless communication technology 15 currently unreliable compared to fixed links The resources of the new wave of mobile terminals are very limited compared to the standard desktop computer Applications aiming at utilizing grid principles on mobile terminals must be able to handle heterogeneous network connections with varying characteristics different types of mobile terminal network disconnections and be conscious
106. dered during the design and implementation Some potential actors are shown in Figure 10 4 Rescue Service Team 1111 A 2 Camera Fish collection barge Figure 10 4 Potential actors in an extended SCG domain As shown both the fish collection barge arriving to harvest the produced biomass and the coast guard which may be enforcing local law may be interested in access to the 119 SCG A Distributed Sensor Management Network in ActorFrame SCG system and specific nodes The fish collection barge could be interested in accessing the SCS nodes GPS data to automate the procedure of connecting with the sea cage How should this be achieved How general does the design have to be to allow for unknown actors to easily and seamlessly interact with the system Some standard interfaces and access methods must be implemented in addition to publicised Perhaps this can be handled by a central SystemAccessEdge actor which further interacts with a services and registry actor Or could it be simpler and more efficient if each system node could provide access capabilities to enquiring actors Yet another option could be for the mobile actors to provide their own interface for the system to utilize simply demanding a generic interface handler on behalf of the application Perhaps the integration of Bluetooth support into the ActorFrame fra
107. des les 101 9 3 AVEBINTERFACE nnb aiuta tel n tees 102 9 4 SETTING UP THE DEMONSTRATOR 2 41224 2 00001000000000000000000000000000000000500500 104 9 5 TESTING zen htt eem niai pendit md ea iss 106 eye e ee 107 9 5 2 experiences from 108 DISCUSSIQ NN ise eu to ea oet ton e eR SE RS sues Hd ae YU sa Rea e Ue a des o 111 10 1 EXPERIENCES FROM DEPLOYMENT DEMONSTRATOR 111 10 1 1 ActorFrame in the SCG domain eese ete tite nensi tana aene e 111 10 1 2 ei mE 113 10 1 3 Rnisesc ee e n E 114 10 1 4 Redundant communication 115 102 DESIGN DECISIONS secession oe eI 115 10 3 NEW FEATURES AND EXTENSIONS 118 10 4 SRUTURE WORK recon ee ce ec rr i ccc Bh ce c 121 CONCLUSION E 125 0 a D HORDE E 127 APPENDIX A 2 133 SCG A Distributed Sensor Management Network in ActorFrame APPENDIX B SYSTEM TESTING osiesessicciccsncscasccbeccosessossesechoscoccounsessosbessaccesesoasoesasonessesestenss
108. e lifetime of the actors such as the GPRS connection of the demonstrator During the period of time which the SCS node is using the GPRS connection only one way communication was possible If the SCS node does not receive the same IP address when the PCS comes back online this situation will not change This is not a preferable option This can also pose problems when the node computer is behind a 113 5 SCG A Distributed Sensor Management Network in ActorFrame firewall or NAT demanding knowledge of the port forwarding scheme implemented One extension could be to allow ActorRouter to read IP headers on received ActorMessage packages As mentioned in the previous section these issues can to a certain degree be handled by the ActorFrame application but this requires access to the ActorRouter settings in runtime An example of this is identifying and updating the IP address of the SCS node when it switches to the GPRS connection of the ECS enabling the MS node to send messages to the SCS It would also be interesting to be able to specify several default gateways both to improve reliability through redundant gateways and to provide several alternate options when links fail The issue of firewalls blocking requests for TCP and UDP connections from outside the LAN was also a problem One option is to maintain the established TCP and UDP sessions beyond that of sending a single signal If the initial request is made by the node res
109. e 136 A TESTING THE SYSTEM loosed ege terere a to vetus 136 B RESTING SENSOR UPDATES a ee E E S 137 TESTING SENSOR AND PCS FAILURE 138 TESTING COMMUNICATION BETWEEN SCS AND MS UNDER 139 APPENDIX C DATABASE 5 141 THE DATABASE COLUMNS AND TYPES ccssssssscecececsessaecececeesensaaececccecsensaaececececsensaaeaeeeeeceenes 141 B DATABASE QUERY SENTENCES cer 8 re rne e 142 APPENDIX D THE SQLINTERFACE CLASS ecce ee ee ee een sesto stans etae s ease tete 144 APPENDIX E THE WEB INTERFACE CODE 155 APPENDIX F THE 858 1 nass see sensn 158 APPENDIX STATE MACHINES 20 0 0 160 A SCSAGENDA 1 A uibs 160 B CSAGENT M 164 MSAGENT 166 APPENDIX LIST OF SIGNALS shovoscssoahessaseanocsesvasoussncecesossesses 170 APPENDIX I IMPEEMENTAT ION o ii eo eva so soo ka eo eo vo o Gode Cn d poe no eoa D eo 173 vii 5 SCG A Distributed Sensor Management Network in
110. e 8 11 The SCSAgent actor design 54 SCG A Distributed Sensor Management Network in ActorFrame The connected mobile terminal will then have access to all the SCS node s capabilities and if desired the rest of the Sea Cage Gateway system Access could for several reasons be restricted amongst others for security issues The SCSAgent actor contains five inner actors which are SCSControlAgent actor The SCSControlAgent actor represents the main logic of the SCSAgent actor This actor handles sensor input parameter distribution and handles the essential data from sensors such as position alerts It also reports and answers to its superiors in the SCG hierarchy SCSDataAgent actor The SCSDataAgent handles the shared persistent data required in the SCS node This could be any way of storing data It is only available through the SCSControlAgent so that a certain level of access control can be implemented If necessary this actor can function towards a database Since only a GPS receiver is used in this system there is no need for a SCSDataAgent actor for the demonstrator and it has therefore not been implemented OSAPIAgent actor The OSAPIAgent actor handles interaction with the local operating system and provides a layer from the residing operating system and the rest of the actors Examples of interaction with the local OS could be to set the node to sleep or to obtain system information such as battery leve
111. e 8 9 The communication schemes of the SCG system There are two ways in which a broken communication link can be detected one from either side of the link In this system only one side can initiate the reserve communication technology If the PCS between the SCS and CS is down only the SCS can handle this by initiating the ECS The CS may detect that it has lost contact with a SCS but can do nothing more than report this to the MS node and request a repair team It is therefore important that both sides of the collaboration implement link connectivity awareness The above also applies for the link between the CS and MS In addition to the failure of links the nodes may also fail This will not be considered in this thesis but the response will be quite similar to that of a servered communication link only that an additional test of node existence is conducted For all signals traversing communication links timers will be incorporated due to the asynchronous nature of the signals The timers can either initiate a second attempt at sending the signal or trigger a fail mode operation Care should be taken and timers should be set long enough to ensure that duplicated signals do not arrive at the destination Although these could simply be ignored and have no impact there is a possibility that duplicate signals can cause inconsistencies The actions taken for each scenario of a communication link failure not the FCS failure are shown in an
112. e Img 1062 0003635 jpg Picture of a flexible fish cage Copied 27 04 2006 from URL http www aquafind com images Cobia24 pg The research council of Norway Innovation Norway Large scale programmes Aquaculture 2020 Transcending the Barriers as long as January 2005 ISBN 82 12 02025 8 URL http www forskningsradet no bibliotek publikasjonsdatabase R Dalton US pushes fish farming into deep water Nature Nature Publishing Group Vol 420 05 12 2005 p 451 URL http www nature com nature AKVASmart ASA Home Page URL http www akvasmart no The SeaWatch project Home Page URL http www oceanor no products seawatch htm K A Hogda Malnes Use of Radarsat F5 images for detection and positioning of fish cages NORUT IT AS International Geoscience and Remote Sensing Symposium IGARSS v 5 2002 p 3047 3049 J A Gredal Paaske Context Aware Services in Aquaculture Fish Farm Monitoring System Master thesis ITEM Telenor R amp D NTNU Spring 2006 S Madden M J Franklin Fjording the Stream An Architecture for Queries over Streaming Sensor Data Proceedings International Conference on Data Engineering 2002 p 555 566 AkvaSensor Camera Smarteye viewed 29 05 2006 127 SCG A Distributed Sensor Management Network in ActorFrame 14 15 16 17 18 19 20 21 22 23 24 25
113. e sensor web to all other integrated nodes This sharing of information is the source of the rich functionality achieved in a sensor web The web itself is one of the end users of the sensor web Information collected and utilized by the sensor web enables dynamic and efficient sensor configuration sensor web management and adaptability For the SCG system this could be of interest in many areas If one node registers an increase in wind speed beyond the normal values it can alert the other SCS nodes of this and these could increase the polling frequency on the GPS position since the weather is expected to worsen Or an increase in algae levels could cause all SCS nodes to increase the frequency of reading these sensors This can also work the other way around by reducing the polling frequency of a GPS reciever when conditions are calm saving battery power Taking it a step further this could handle sensor loads and configuration by adding context and load information 12 4 4 Utilization and distribution of sensor information The vast amount of sensor information standing to be acquired through the wide spread use of a system such as the SCG system can be of use for many parties beyond the fish farm company itself Such factors can affect what type of data could be of interest and influence the way the sensors are set up both in regard to the information retrieved and the way it is handled Some interested parties and their possible are
114. ed amongst the remaining SCS nodes forming a type of virtual CSAgent minimizing the affect of such a failure on the rest of the system Another interesting area is work on improving data sharing amongst the nodes of the SCG system the sensor web inspired functionality Providing the ability to interpret sensor data collected from other entities to improve operating parameters for the node and equipment itself As already mentioned registered occurrences or sensor readings warranting an increase in the polling frequency of the sea cage position could be of interest Increases in wind speeds or currents drops in pressure or increased sea cage velocity are all elements which can trigger the SCS node to reconfigure the settings of its GPSControlAgent actor Another interesting application area is that of poisonous algae If one sea cage detects an increase in the algae amount in its vicinity this information can immediately be sent to the MS node CS node and all other local SCS nodes This can allow if the sea cages are submersible for SCS nodes to adjust there buoyancy of their sea cage and retreat to depths clear of the algae A quick reaction to such threats could save enormous values The possibilities and scenarios for this are next to endless It could also be interesting to implement further edges to improve accessibility to the system One such edge could be towards Web Services others could be connecting the SCG system for system initiat
115. egistration of new nodes CS and SCS a The system must make information about new OK Failed nodes available to other nodes The new nodes must receive information OK Failed about the other nodes in the system c The SCG system must register all nodes OK OK 2 The system must allow for information to OK OK 107 SCG A Distributed Sensor Management Network in ActorFrame be propagated throughout the system Parameters must be available upon initiation OK OK Basic parameters must be possible to update OK OK upon initiation 3 The system must detect and handle OK OK communication link failures If MCS fails between CS and MS FCS must Not Not be used implemented implemented b If PCS fails between CS and SCS ECS must OK OK be used PCS and FCS fail ECS must be Not Not used implemented Implemented 4 The system must issue alerts upon sensor OK OK value deviation or PCS failure Upon failure maintenance team must be OK OK notified b Upon alarms rescue team must be notified OK OK 5 The system must collect and store sensor OK OK data a Data must be retrieved from sensors and OK OK provided to other nodes upon requests 6 The system must utilize sensor data to issue OK OK warnings about abnormal sensor readings a The system must issues warnings regarding OK OK deviations in the GPS readings against pre
116. eillance principles and communication technologies In addition it is a goal to keep the elements as low cost as possible to secure maximum deployment and utilization for as many actors as possible This thesis has been an interesting and informative task It has taken me through many fields of my education and provided a perfect mix of both practical and theoretical elements I would like to thank my fellow students Frank Paaske and Jon Arne Gredal for much help and advice I would also like to thank Geir Melby Haldor Samset and Frank Kramer for always answering my questions Furthermore the World Cup and Tour de France deserve a mention for their many distratctions Finally I would like to thank my supervisors Rolv Brak and Frode Fl gstad for much understanding help patience and feedback throughout the duration of this thesis Trondheim August 2006 Jens Askgaard iii 5 SCG A Distributed Sensor Management Network in ActorFrame SCG A Distributed Sensor Management Network in ActorFrame Table of contents SUMMARY eee eoo ste evene suero 1 PREFACE 44450 606 900000415 604169060006 TABLE OF CONTENTS V IB C Ix EIST OBR TABE Dc svedessdsetesossdeees 060415450066 610444466 XI ABBREVIA
117. ellow else System out println The CS status has not gone to yellow catch Exception System out println Problem e toString finally seme ONSE try stmt close catch Exception e System out con puli try con close catch Exception e System out println e toString con mudi p public void setCsStatusRed String csname throws Exception Connection con null Statement stmt null int affected 0 try String url scgdb Class forName com mysql jdbc Driver newInstance con DriverManager getConnection url user komtek stmt con createStatement affected stmt executeUpdate UPDATE CS SET statusid 3 where csname csname 1 System out println The CS status has gone to eise System out println The CS status has not gone to red catch Exception System out prinbEln Problem e toString finally 4 ir sime try d stmt close 149 SCG A Distributed Sensor Management Network in ActorFrame catch Exception e System out prankiln e stmt nuli conem con close catch Exception e System out println e toString con null public void s
118. ensor data High Data must be available for retrieval at a later occasion High 6 The system must utilize sensor data to issue warnings about High abnormal sensor readings a The system must issues warnings regarding deviations in GPS High readings against pre defined threshold values The system must issues warnings regarding failed communication High links and nodes Points one and two are partly inspired by mobile grid concepts by providing all nodes with access to all other system nodes through the distribution of address lists Through these lists mobile nodes can interact and gain access to the systems capabilities Inspiration from the sensor network architecture is used for minimizing energy use and resource consumption among distributed nodes and although the utilization of sensor data among other nodes is beyond the scope of this thesis the architecture is to provide a basis for incorporating the principles These points also imply a certain level of self configuration on initiation of SCG elements Point three deals with the fault redundancy element of the system and point four includes the possibility of complete node failure Point five addresses the issues of data handling and point six provides definitions of a few ways to handle sensor data slightly inspired by sensor networks Being only some functional requirements of a system with limited functionality most of the requirements have a high priority One exc
119. eption is the node presence distribution as this does not directly affect the services required They simply lay the foundation for more advanced services The other exception is the handling of link failures between the CS and MS node As the equipment necessary for such 43 5 SCG A Distributed Sensor Management Network in ActorFrame functionality is lacking in the demonstrator their priorities have been set to low This is to focus on the issues at hand with the equipment available This is not an exhaustive list of requirements simply a foundation for displaying the requirements and design goals the rest of the system can be built on and utilize This is the case for requirements 1 amp 2 where the propagation of information and actors provide the possibility for both self configuration techniques and mobile grid functionality 8 1 2 Non functional requirements After establishing the functional requirements the nature of the non functional requirements must be identified and specified Issues such as delay reliability user interaction ease of use cost maintenance and more are all aspects to be considered when designing a system As the system being implemented in this thesis is simply for simulation and demonstration purposes the non functional requirements are often set simply for stream lining the test procedures As complex a system as the SCG system can become especially if providing full mobile grid computing in
120. er SCSManager Figure 8 15 The CSAgent actor design The CSAgent actor consists of seven inner actors The CSDataAgent CSRouter MobileTerminalAgent SensorManager and CSControlAgent represent the same functions as in the SCSAgent actor although there features may be slightly different or extended The reasoning for their existence corresponds with those presented under the SCSAgent section Since there are no sensors attached to the CS node for the demonstrator no SensorManager has been implemented in the CSAgent The SCSManager is responsible for handling all SCS nodes attached to its CS This is done by assigning a SCSSession actor to each connected SCS This is shown in Figure 8 16 58 5 SCG A Distributed Sensor Management Network in ActorFrame SCSManager lt lt Actor gt gt SCSSession Figure 8 16 The SCSManager actor design The SCSSession actor handles interaction with its specific SCSAgent throughout the period the SCS is connected to the CS This provides dedicated actors handling each SCS connected to the CS and provides a layer between the CS and its SCS nodes 8 3 3 MSAgent The MSAgent represents the MS node of the system Its structure is shown in Figure 8 17 As presented in section 8 2 3 a possible set of tasks for the MSAgent actor have been established This list could of course be extended a context handler could be added to the system for instance Alternatively such functions and o
121. erMsg RouterUpdateTimerMsg RouterUpdateTimerMsg y 1 Figure 7 8 An informal sequence diagram illustrating ActorRouter protocol After receiving the ActorRouterRegMsg signals from all actors the ActorRouter reports to its default gateway every ten seconds not shown When a local actor sends a message to an actor not present on the node the signal is sent to the local ActorRouter Here the forwarding table is checked to see if the recipient has been registered and if not present than ActorRouter sends the message to its default gateway The ActorRouter table residing on the default gateway address then handles the message If it is not present here the signal is resent to its default gateway Eventually the recipient is found or the message is discarded No notice of a discarded message is given by ActorRouter The process is shown in Figure 7 9 Note that the process presented assumes that the residing actors on a node have not been reported to the default gateway so the ActorRouter table of ActorDomain B does not yet contain those of ActorDomain A 35 SCG A Distributed Sensor Management Network in ActorFrame ActorDomain C Public IP 129 xx xx 03 Default Gateway 129 03 ActorDomain Public 129 01 Default Gateway 129 xx xx 02 ActorDomain B Public IP 129 xx xx 02 Default Gateway 129 03 6 Message Receiver Actors a
122. es as it is not uncommon to want to distribute ActorA ddresses either by specifying the target or originator of a signal which must traversed other actors before reaching its destination It would also be interesting to see if Ramses could provide the possibility to set a signal reception to all existing states scenario where this could be useful is the event of a link failure or when a sea cage is drifting when priority messages must always be handled As one of the nodes of the SCG system was run on a Linux platform Ramses was run on this platform Although initially platform independent there were problems with using Ramses on Linux This was solved by creating a tmpactordir in the root directory Finally it was experienced that Ramses development tool became increasingly unstable when the system generated increased in size and complexity This grew to such an extent that further implementation and some design changes went unimplemented It is for the time being unclear if the problem was due to Ramses ActorFrame Eclipse the development computer or any of the plug ins which Ramses utilizes 10 1 4 Redundant communication link The redundant communication link for the demonstrator was provided by a GPRS modem This modem was set up at a speed of 115 2 Kb s The data rate provided was more than adequate to provide the communications necessary and the link could be initiated and disconnected upon request A slight increase in la
123. es must be considered when setting the timer interval The SCS node now automatically generates position reports and sends these directly to its CSSession actor This is shown in the communication diagram presented in Figure 8 49 comm The SCS reporting position data when using ECS 1 SCSGPSSensorData 1 1 SCSGPSSensorData TY SCSAgent MSAgent Database Figure 8 49 A high level communication diagram for sensor reporting with ECS 87 SCG A Distributed Sensor Management Network in ActorFrame The signal GPSSensorData has now been replaced with SCSGPSSensorData for reporting the SCS node s current position The reason for this is that part of the natural hierarchy used for signal distribution is gone so the signal sent by the SCSA gent requires more information than previously required under normal operations Subsequently position deviations must now also be reported in to the CSSession actor This follows the same pattern as during normal operations except that the CS node is not involved and that the SCS node sends a PosAlertForSCS signal instead of PositionAlert This signal has been replaced for the same reason the GPSSensorData signal was changed A communication diagram for this procedure is shown in Figure 8 50 comm The SCS registers a position deviation when using ECS 1 1 PosAlertForSCS SS Database 1 PosAlertForSCS gt SCSAgent MSAgent
124. ese elements are shown in Figure 3 2 Sea Cage Gateway Figure 3 2 Communication schemes of Sea Cage Gateway The features of the communication schemes are shown in Table 3 2 10 SCG A Distributed Sensor Management Network in ActorFrame Table 3 2 The proposed communication links of the Sea Cage Gateway System Communication Description link Main The MCS is the primary broadband communication Communication technology connecting the CS to the MS System MCS Primary The PCS is the primary broadband communication technology Communication connecting the SCS to the MS System PCS Failure The FCS is a backup narrowband communication technology Communication which goal is to maintain communications between the MS System FCS and CS in the event of a MCS failure This technology should provide other characteristics then the MCS technology Emergency The ECS is a backup communication system which provides Communication communication in the event of a failure in the PCS between System ECS the SCS and CS It also provides a backup in the event of a complete communications failure in SCG which is a complete failure of both the FCS and PCS Since the backup communication schemes have different characteristics than the primary communication technology an extra redundancy is implemented in the system However this also implies that the information flow sent in the two cases ca
125. etScsStatusYellow String scsname throws Exception Connection con null Statement stmt null int affected 0 try String url Wdbesmysql scgdb Class forName com mysql jdbc Driver newInstance con DriverManager getConnection url user komtek stmt con createStatement affected stmt executeUpdate UPDATE SCS SET statusid 2 where scsname scsname a y System out println The SCS status has gone to yellow else System out println The SCS status has not gone to yellow catch Exception System out prinEln Problem etostring finally stmt I try stmt close catch Exception e System out println e toString semt nuli con TS ing d con close catch Exception System prinkin e tostring con null public void setScsStatusRed String scsname throws Exception Connection con null Statement stmt null int affected 0 try String url 7 1 Class forName com mysql jdbc Driver newInstance con DriverManager getConnection url user komtek stmt con createStatement affected stmt executeUpdate UPDATE SCS SET statusid 3 where scsname scsname i System out println The SCS status has gone to red
126. eters Table 6 1 Communication link characteristics and areas of application Communication Range Licensed MCS PCS ECS FCS Data technology spectrum rate max GPRS High YES No No Yes Yes 160 kb s CDMA450 High YES Yes No Yes Yes 2 Mb s WLAN Low NO Yes Yes No No 20 Mb s WIMAX Medium YES Yes Yes Yes Yes 2 Mb s VHF Data High YES Yes No Yes Yes 140 kb s Satellite Global YES Yes No Yes Yes 8 Mb s communication When considering the suitability of a communication technology to the requirements of the four links defined for the SCG domain range and data rates are the most obvious characteristics The PCS requires least range but may require larger capacity due to the amount of communicating nodes present The ECS requires the largest range of all This is not only because it is the element farthest from land but because it must also provide communications in the case of a moorage breaking This can quickly bring the sea cage far out to sea The FCS and MCS are supposed to cover the same distance assuming that the CS node the frame and all the SCS nodes do not begin to drift Most technologies are easily interconnected with WLAN through an Ethernet connection For PCS WLAN is the obvious choice For the other connections there are no clear technologies which stand out above the rest In addition several more factors about the data rate capacity an
127. f design Figure 2 2 A rigid sea cage 4 A flexible sea cage is shown in Figure 2 3 As shown these constructions differ in many ways from the rigid design There is a lack of personnel access and the construction is not stable Although this reduces user accessibility there are many advantages with this form of design and it is the most common construction used Figure 2 3 A flexible sea cage 5 The flexibility of the design enable the construction to withstand rough conditions conditions often experienced in the offshore waters of coastal Norway The construction is also lightweight and cheap These factors affect both the economic side but also allow for simpler logistics and delivery in isolated areas Sea cages also vary between being a floating cage or submersible As the name implies a submersible cage is enclosed in all directions and can be sunk below the seas surface when needed This can be an advantage during rough conditions protecting the cage itself the environment and its contents SCG A Distributed Sensor Management Network in ActorFrame Sea cages are provided feed through the use of feed barges spraying food into the enclosure at regular intervals or through fixed pipes mounted to the cages attached to a central feed unit A mobile feed barge is shown in Figure 2 4 Figure 2 4 A mobile feed barge by a sea cage 6 Although sea cages present a good way of rearing fish there are prob
128. for the MCS of the SCG system It should be noted that field tests in Chile with WiMAX transmissions over the ocean surface have not been promising The links are very unstable which to a large degree is due to transmission interference because of reflection of the signals from the sea These factors can also affect the range of the similar WLAN technology An improvement has been achieved by placing the transmitting and receiving antennas higher up in the air thus changing the angle of which the radio waves hit the sea surface 35 6 7 Bluetooth Bluetooth is a wireless radio standard with focus on low energy consumption It currently exists in three standards with communication ranges from 10 cm up to 100 metres and it can support communication speeds up towards 2 1 Mbit s It is able to discover other Bluetooth units in their vicinity through the use of a Service Discovery Protocol 36 Whilst WLAN is considered a wireless version of wired Ethernet LAN s Bluetooth s area of application has been considered to replace cables currently used between a computer and its accessory units Bluetooth is included here not as an alternative for either the narrowband or broadband communication but because of its Service Discovery protocol This property is of value when it is necessary to automatically discover the presence services and capabilities of nodes This could be a function to ease the implementation of mobile nodes interacting directly wi
129. g Info Centre FAQ Gridcomputing com viewed 4 7 2006 URL http www gridcomputing com gridfaq html Wikipedia org Grid computing viewed 6 7 2006 URL http en wikipedia org wiki Grid computing Y Wen Mobile Grid Major Area Examination Department of Computer Science University of California URL http pompone cs ucsb edu wenye majorexam writeup pdf Telenor Mobile Dekningskart viewed 26 6 2006 128 SCG A Distributed Sensor Management Network in ActorFrame 26 27 28 29 30 31 32 33 34 35 36 37 38 39 URL http telenormobil no dekninginnland index do Ice no Homepage URL http www ice no Ice AS Coverage map for CDMA450 viewed 29 6 2006 URL http www ice no IEEE 802 11 Standard available at URL http www 1eee802 0rg 11 Homepage of Telenor Satellite Services URL http www telenorsatellite com Telenor Satellite Services Sealink Home Page URL https www telenorsatellite com files 5Ccontent 5Cdownload 5Ccontent8 0 5CSealink TSS Eng 16 03 05 pdf Telenor Satellite Services SeaLink telenor no URL https www telenorsatellite com index cfm oa product display amp pro 33 Telenor Maritim Radio Pressemelding Telenor Maritim Radio lanserer Data Telenor telenor no viewed 3 7 2006 URL http presse telenor no PR 200605 1048383 1 Halvorsen
130. ge actor provides an edge to a WAP gateway to enable WAP specific functions much like those of the SMSEdge actor This edge has not been implemented as the alarm function is sufficiently demonstrated with the SMSEadge httpEdge actor This actor holds a reference to a web server for interaction with web users through a web interface The advantages of using web interfaces for user and control interaction are many Through the use of web pages web browsers can access the information from anywhere and to a certain extent remove the necessity of local applications residing on user machines To handle the statelessness of the http protocol AttpSession actors are implemented as an inner actor of the httpEdge actor as demonstrated in 49 This actor has not been implemented as this form of interaction is not the focus of the design 62 SCG A Distributed Sensor Management Network in ActorFrame AdminEdge actor In order for an administrator to adjust change parameters and functionality of the system an actor provides an edge against a user interface most likely a GUI The AdminEdge is for providing an interface to system for users In this system it will be limited simply providing the possibilities for testing some functionality of the system 8 4 Sequence and communication diagrams Here the main functionality and interaction patterns of the system are described with corresponding sequence and communication diagrams Not
131. gitude are used From GPSInfo class a LatLng class is created with the data from GPSInfo class The reason for using LatLng class is due to the provided distance method This method returns the distance from a provided position compared to its own position variable This makes it possible to set a certain maximum distance away from a pre defined point for the GPSControlAgent actor to allow For instance considering the natural drifting of a cage if a distance from the original position of over fourty metres is unusual an alarm can be issued This distance is just an example The action statement used in the GPSControlAgentActions class 15 shown below The instances newLal and oldLal are of the type LatLng The oldLal instance 1s the default position to which subsequent position messages are compared to The default for the demonstrator 15 set as the first position received after the GPSControlAgent has been created The timer interval has been set to 10 seconds in milliseconds This interval can be altered according to needs When the ReqGPSPosition signal is received by the GPSSensorEdge actor the actor simply calls the retrieveGPSPosition method of the GPSHandler receives a LatLng class and sends this back to the GPSControlAgent 9 2 2 OSAPIAgent WindowsAPIEdge In this system OSAPIAgent handles the interaction with the operating system Since Java is a platform independent language it can be deployed on al
132. gnal As mentioned in section 7 1 1 UML2 0 does not provide separate notations for behaviour and delegation ports In this thesis however behaviour ports will be 32 SCG A Distributed Sensor Management Network in ActorFrame symbolised with a white square whilst delegation ports are shown with filled black squares This is shown in Figure 7 6 DemoActor lt lt gt gt InnerActor lt lt Actor gt gt InnermostActor 221 OtherActor Delegation port Figure 7 6 Distinguishing between delegation and behaviour ports The filled port indicated by the green arrow is a delegation port enabling the InnerMostActor actor to connect directly to the OtherActor The full functionality of ports is somewhat unclear in ActorFrame What kind of behaviour occurs when several instances are connected to same port is uncertain Therefore ports in this system are only used in one to one relationships of static actors and only connectors are used when connecting a dynamic instance to a static actor In the SCG system the service modelling through the use of the play analogy may not be all that obvious Mainly the RoleRequest protocol is intended to be used to provide a level of self configuration of the nodes in the system Actors will represent entities of the system and interact to provide the services required by the system through signal passing and by dynamically adding and removing actors and roles The
133. he UpdateCompleted signal and the timer for requesting sensor updates is reset This timer is set for the first time when the SCG system registers its first sensor A communication diagram illustrating the interactions between the distributed actors is shown in Figure 8 30 71 SCG A Distributed Sensor Management Network in ActorFrame comm MS requests a sensor update Database To all CSAgents 1 3 AddSensorData in turn 1 GetSensorUpdate eM CSAgent MSAgent 1 1 CSSensorDataUpdate Figure 8 30 A high level communication diagram for sensor data retrieval from the CS nodes The sequence diagram showing the interaction between the CSSession actor and its CSControlAgent and CSDataAgent upon a sensor update request is shown in Figure 8 31 sd Collecting CS information css CSSession csca CSControlAgent csda CSDataAgent GetSensorUpdate 1 2 GetSensorUpdate gt CSSensorDataUpdate sensorData CSSensorDataUpdate sensorData 1 I Figure 8 31 The sequence diagram for the handling sensor update requests by the CS The signals presented all go through the CSRouter actor but this is not shown 8 4 2 2 Communication between CS and SCS Asides from the case of abnormal sensor reading leading to the generation of an alert signal communications between the SCS and CS is genera
134. he term Electricity is a readily available product to an almost ubiquitous degree and factors such as point of origin production and transportation methods are completely transparent to the user The final product however is a commodity Such is the vision for processing and storage resources In addition utilizing the enormous amount of latent processing power for research is an area of many opportunities One could eventually see all connected computer resources as one enormous virtual computer with virtually unlimited processing power and resources For the SCG system such visions are far off However grid principles can be included as to increase the power of the implemented architecture The SCG system will be comprised of many sensors and many computer nodes These elements vary in characteristics and power If the combined resources of these resources could be tapped the SCG system could become even more autonomous Although there are many issues to be handled in order to utilize the resources of a distributed system the system design should provide a basis for providing such functionality By building a hierarchy of increasingly more powerful computer nodes whilst making all nodes aware of all other nodes the building blocks for distributing and requesting resources from others are laid All nodes should have the knowledge and capability to communicate with other nodes Grid computing also introduces other issues which must be attende
135. hem and supply them to a proxy for handling 12 The proxy is generally the machine the sensor has been connected to and one proxy will likely administer multiple sensors In general limited resources capability is an attribute to almost all sensors This adheres to processing power memory bandwidth limitation and above all battery capacity Battery capacity is the limit to which all other limits succumb with bandwidth being the largest consumer of energy 4 2 Sensors related to aquaculture Sensors available for aquaculture are many and are currently increasing The need for all of these sensors may not be necessary but support for the majority should be provided Some of these sensors may only be needed on a simple SCS in a frame and this information then can apply for all SCS nodes local to that frame 3 lists the following areas as of interest for utilizing sensors to detect the required parameters weather current temperature salinity oxygen algae nutrients biosensors radioactivity heavy metals hydrocarbons pH In addition sensors monitoring the equipment in use the food consumption and current position of the sea cage can provide the functionality and support required Many of these sensors can be related to the factors influencing the exploitable stock as shown in Figure 2 1 Several of these sensors are available from AK VAsmart 8 and a selection of their assortment is displayed in the subsequent figures
136. here presented The implemented system contains five of these for demonstrational purposes These are the GPSSensorEdge WindowsAPIEdge DBEdge SMSEdge and AdminEdge The SensorDetectionEdge actor has also been implemented but it only requests a GPSSensorAgent containing the GPSSensorEdge from the SensorManager 9 2 10 GPSSensorEdge The GPSSensorEdge actor handles interaction with the GPS sensor incorporated into this system To be able to read and utilize the data generated by the GPS sensor several steps are required First the COM port of the sensor must be established Second the data from the sensor must be read Third the data must be interpreted in order for it to be utilized 9 2 1 1 Acquiring GPS data In order for data to be read from the GPS sensor a connection between the GPSSensorEdge actor and the COM port of the GPS sensor must be made To enable a connection to a COM port via Java an open source library has been used As Sun no longer provides an open API for this purpose with Windows an alternative library was incorporated 56 This is the RXTX library which is a native lib providing serial and parallel communication for the Java Development Toolkit JDK available under the gnu LGPL license 57 The LoggingServer class which provides interaction to the GPS receiver requires the that the GPS receiver is attached to in order to open a connection In this system this is done manually by specifyi
137. his implies that a SCSAgent actor will reside on the SCS node a CSAgent actor on the CS node and so forth The use of the agent name of actors is a ServiceFrame concept extending the actor concept a step further In ServiceFrame agents are an Actor class which publicly represents actors Agents automatically register themselves with a NameServer actor for easy discovery This will not be implemented here only the naming paradigm is used With a basis of utilizing all the nodes in the fashion of sensor webs or in grid computing the possibility of connecting all nodes to each other is an option that should be considered in the system design The vision is that all the SCS nodes are interconnected through their CS and all CS nodes are interconnected through their MS The elements are not physically interconnected directly but the connections are made possible through the distribution of node presence address status and knowledge throughout the system 5 For the remainder of this thesis all ActorFrame actors and signals will be represented in an italic font 39 SCG A Distributed Sensor Management Network in ActorFrame Figure 8 1 Interoperability between nodes mobile grid To enable a scalable solution to the addressing issues the grid web is built up as a hierarchy using the natural hierarchy already implemented in the relations between the nodes The cardinalities of these relations are shown Figure 8 2 d
138. his thesis has further investigated the possibility of remotely controlling and administering a fish farm through distributed nodes over wireless communication links As a basis for this thesis domain descriptions from previous master theses written in connection with the SCG project have been used This thesis has also aimed to collect inspiration from other domains and concepts which have similarities with the SCG project With the increasing numbers of nodes and communication links present at the fish farm installations areas such as grid computing and sensor networks have many applicable principles for the SCG system These principles have been integrated into the system design to give the basis for further such functionality in the SCG domain In addition to the areas of grid computing and sensor networks the current and latest wireless communication technologies available for providing the services required by the SCG system have been presented The communication links also influence the system design since their connection types must be handled by the SCG system elements The SCG system proposed has been designed and implemented with ActorFrame The implemented system has functioned as a demonstrator for the main principles presented in the design It has incorporated a GPS receiver and a GPRS modem to represent a sensor on a sea cage and a redundant communication link The system implemented reports GPS data to a central unit and issues alerts
139. his thesis it has been named ActorRouter so it is not to be confused with Router actors 34 SCG A Distributed Sensor Management Network in ActorFrame instance if one is residing behind a NAT with private addresses then the port forwarding scheme must be known The default gateway is the IP address where messages recipients not present on the local node are sent An ActorRouter instance upon request resides on each node where actors exist An actor is made visible to ActorRouter by calling the method setVisible true in the actors state machine ActorSM class which allows for a local actor to be registered by ActorRouter The default is that an actor is not visible After a set time interval by default 40 seconds each actor reports to their ActorRouter and then the ActorRouter reports to a default gateway which actors reside on its domain This is shown in Figure 7 8 a A b A c a ar ActorRouter dg ActorRouter el al RouterUpdateTimerMsg RouterUpdateTimerMsg RouterUpdateTimerMsg 1 1 1 1 1 1 1 1 ActorRouterRegMsg ActorRouterRegMsg ActorRouterRegMsg _ 1 1 H 1 1 1 SET NOW time SET NOW time SET NOW time ActorMsg myActors 1 1 1 1 1 1 1 1 RouterUpdateTim
140. hoc connecting of sensors in a SCG gateway environment is beyond the scope of this 17 SCG A Distributed Sensor Management Network in ActorFrame thesis but issues within mobile ad hoc sensor networks can be applicable to the domain in question The main challenges with low energy sensors in ad hoc wireless networks are mainly the same as in sensor networks energy conservation limited computational and memory resources and bandwidth requirements In addition mobile ad hoc sensor networks must handle wireless communication within a dynamic topology One area of research is the data link layer utilized in a mobile ad hoc sensor network Focus is on using contention free protocols such as TDMA to reduce power consumption at sensor nodes 19 The range a node transmits its data can also be adjusted ensuring that the node does not exaggerate the distance it sends its information thus preserving energy Another focus area is balancing the trade off between sensor computations on data or sending data to another node for computation The main power drain for a wireless sensor node is the transmission of data so in some cases a few extra cycles of the CPU uses far less energy then transmitting the data It is also less energy intensive to receive a wireless transmission than to broadcast one 18 For the SCG system this can provide some guidelines Although the data link layer used is not part of this thesis avoiding contention
141. hods on distributed actors has already been commented in section 9 5 2 This should be attended to in order to ensure consistent addresses throughout the system It may be that ActorFrame does not discriminate between the two forms of addressing but it could pose a problem for external applications In the demonstrator this caused problems with the database entries This form of addressing actors may provide a possible way of dynamically specifying an actor s IP address in an ActorMessage but such a solution should probably be avoided One of the SCG domain goals is to provide the cheapest solution possible By using Java as a programming language platform impendency of the residing operating system is achieved This allows for the use of for instance Linux for the operating systems of the nodes in the system Unfortunately the system does not achieve full platform independency due to the fact that the application needs access to services only available through the native operating system In the demonstrator this has been in relation with the connection of the GPS receiver and GPRS modem both which have been given Windows specific implementations A sign of this lacking cross platform independence is the introduction of the OSAPIAgent actor into the system design to hide this from the rest of the ActorFrame application It is not feasible for ActorFrame to provide interaction with all operating systems but in certain areas such functionality c
142. iable response times since the request does not propagate throughout the system but also for ensuring up to date sensor data in each independent node This is important in the case of communications failure It also allows for data to be aggreagated at several natural levels before being reported further When the sensor data has been reported upwards in the SCG hierarchy the local sensor data registry can be emptied or perhaps stored in another format for backup reasons This has not been considered here The sequence diagrams for the collaborations illustrated above are described in detail in the following sections 8 4 2 1 Communication between MS and CS Communications between the CS and MS can be initiated for a variety of reasons due to an alarm regular sensor data update or upon request from a user The request can 70 SCG A Distributed Sensor Management Network in ActorFrame be generated either by user through the AttpEdge through the AdminEdge or through a regular timer for retrieving the data from the SCG system nodes This in turn generates a GetSensorUpdate signal to the CSManager actor who proceeds to query all its CSAgents for their sensor data The CSAgents are registered in a csList which is an ArrayList The sequence diagram for this is shown in Figure 8 29 sd Initation of data collection from MS ae AdminEdge he httpEdge msca MSContr
143. iding behind the firewall all responses will be allowed to return This does however require that the one node always makes the first initiative but it does enable firewall traversal These proposed extensions will to a certain extent remove the transparency to networking issues otherwise provided by ActorRouter The increasing variety of network connections and technologies with mobile nodes constantly re establishing connection points makes it difficult to make the network layer completely transparent Since this is difficult for a framework to handle the application layer must be aware of network layer and aid in the process of handling this This is an unfortunate measure but necessary to explore in order to fully utilize the potential of full mobility and heterogeneous network technologies 10 1 3 Ramses The Ramses tool suite has been used for implementation of the system designed It provides the possibility for inserting the design directly into the tool and then automatically generating the code This has greatly simplified the implementation process making it both quicker ensuring correctness and providing support for testing In the domain of model driven development Ramses is a tool which greatly improves and aids such a system development process Still there are some are some possible areas of improvement and extensions that would increase the Ramses tool suite efficiency One area is providing the possibility of using inhe
144. ign The trace viewers show message sequences for testing and error detection The generator translates the system design into code Ramses has been used to implement and check the SCG system designed in this thesis A screenshot demonstrating the model view used by Ramses is shown in Figure 7 12 Java GuidanceSystem Eclipse SDK Dex Ele Edt Navigate Search Project Ramses Run Window Help re 0 6 7 Package Explorer 7 virtualcorridorac 7 UserNotificationa 7 RouteAgentsM java 69 GuidanceSession Guidancesystem 22 iz ELI E 127 no ntnu item project2005 guidancesystem 1 0 0 GuidanceSystem 18 model uml no ntnu item project2005 actors guidancesystem GuidanceSystem no ntnu item project2005 actors positionagent no ntnu item project2005 actors positionedge E no ntnu item project2005 actors routeagent no ntnu item project2005 actors terminal no ntnu item project2005 actors terminalagent no ntnu item project2005 actors useragent GuidanceSystem ua UserAgent O r LiteRouteAgent orridor Routelnfo getRouteData RouteChoice ta Termalagent 0 registerGS RoleConfirmMsg p izkoPositionAgent 9 registerUAandGetRoutes InitGuidanceSession requestNewRoutesStopVC ArrivedAtDestination sendRoutelnfo RequestRoutelnfo sendRoutesToTA AvailableRoutes currentPositi
145. il no kundeservice teknisk Sun Microsystems Java Communications sun com URL http www sun com download products 43208d3d xml K Jarvi The RXTX homepage URL http www rxtx org U Walther JavaGPS Information Page URL http javagps sourceforge net J Stott jcoord Home Page URL http www jstott me uk jcoord MySQL Download Page URL http dev mysql com downloads mysql 5 0 html L Ullman VISUAL QUICKSTART GUIDE MYSQL SECOND EDITION Peachpit Press 2006 ISBN 0 321 37573 4 MySQL Connector J Download Page URL http www mysql com products connector j Wikipedia org Web Service viewed 18 7 2006 URL http en wikipedia org wiki Web_ service Sun Developer Network JavaServer Pages Technology Sun Microsystems Inc URL http java sun com products jsp PHP Hypertext Processor Homepage URL http www php net J J Garrett Ajax A new approach to web applications adaptivepath com 18 2 2005 URL http adaptivepath com publications essays archives 000385 php Blazix The terms and conditions for use and downloading of Blazix Blazix home page URL http www blazix com download html Blazix Advanced Java Application Web Server Blazix home page URL http www blazix com H Meling A Montresor The JGroup ARM Dependable Computing Toolkit presentation The JGroup ARM project UIS NTNU University of Bologna
146. ilure detected by MS csr CSRouter gm GroupManager GetSensorUpdate SET NOW time connectionTimer GPSSensorData position 1 1 STOP connectionTimer L connectionTimer MCSFailed cs gt MCS failure detected by CS Figure 8 44 The sequence diagram for a failure of MCS between MS and CS When the MS detects a failed communication link to a CS it can do little more than alert the correct personnel about the failure In order to restore communications the CS must itself become aware of the link failure and switch to FCS communication This is shown in Figure 8 45 83 5 SCG A Distributed Sensor Management Network in ActorFrame sd MCS failure detected by CS css CSSession csr CSRouter cscs CSControlAgent osapie OSAPIEdge ConnectionCheck 1 1 1 1 connectionTimer 1 ConnectionCheckRep gt STOP connectionTimer SS Mit connectionTimer MCSDown gt InitFCS FCSInit 1 Figure 8 45 The sequence diagram for a failure of MCS between CS and MS As previously mentioned the procedure here is very similar to when a SCS switches to ECS Here the initiation of the GPRS link is done if the FCS is GPRS and a report of the situation is sent to the MS node s CSSession which will then take the appropriate measures for re establishing the link 8 4 3 3 Failed FC
147. ined The functional requirements presented can also be viewed as design goals for the system These requirements are based on the keywords presented in the scenario in section 3 1 1 and on the sensor network and mobile grid concepts discussed in sections 4 3 and 5 1 These are listed in Table 8 1 42 SCG A Distributed Sensor Management Network in ActorFrame Table 8 1 Some basic functional requirements for the SCG system SR Description Priority 1 The system must allow for automatic configuration and High registration of new nodes CS and SCS The system must make information about new nodes available to Medium other nodes The new nodes must receive information about the other nodes in the Medium system The SCG system must register all nodes High 2 The system must allow for information to be propagated High throughout the system Parameters must be available upon initiation High Basic parameters must be possible to update upon initiation High 3 The system must detect and handle communication link failures High If MCS fails between CS and MS FCS must be used Low b If PCS fails between CS and SCS ECS must be used High PCS and FCS fail ECS must be used Low d Upon failure maintenance team must be notified High Upon alarms rescue team must be notified High 5 The system must collect and store s
148. informal sequence diagram shown in Figure 8 10 51 5 SCG A Distributed Sensor Management Network in ActorFrame sd Failure modes overview scsaSCS cs CS ms MS 1 1 1 1 1 1 1 1 1 Report Timer 1 LinkSCStoCSDown gt Report EssentialData 1 gt Report 1 1 1 i Timer 1 1 1 1 K ReportLinkDown scsID 1 L 1 4 gt gt 1 1 1 Timer 1 1 LinkCStoMSDown Report EssentialData gt 1 1 T a T 1 1 Report 1 1 1 1 1 1 Timer PM 1 1 1 i MStoCSDown 1 1 1 Figure 8 10 sequence diagram showing failure of different communication links In the first alternative of the sequence diagram a failed PCS between the SCS and CS results in a switch to ECS and a report is made to the MS node Since the communication links are in essence transparent link failures only manifest themselves in the system as a change of addressing the recipient of a signal This applies only to the SCS node where a primary link failure leads to an alternative addressing node and signals are sent to the MS node Another problem does arise though Upon initiating a new communication link the node will receive
149. ing scsname String CSGPSSensorData position String Add code for serialization of scs ActorAddress SCS CSList otherCS List ArrayList CSPCSDown CSRegistered csList ArrayList ConnectionUpdateRep ConnectionUpdateToMS ECSInit FCSInit GPSPositionUpdate lal LatLng GPSSensorData position String Add code for serialization of scs ActorAddress SCS GetCSSensorUpdate GetSCSSensorUpdate GetSensorUpdate InitECS InitFCS NewSCS newSCSS Add code for serialization of ActorAddress newSCSS NewSensor sensorType String PCSDown PCSRestored PosAlertForSCS alertSCS Add code for serialization of ActorAddress alertSCS currentPos String PositionAlert currentPos String RegisterCSInfo RegisterMS yourCSM ActorAddress RegisterSCSInfo ReqGPSPosition 170 SCG A Distributed Sensor Management Network in ActorFrame ResetDefaultGPS Position scs ActorAddress SCSConnectionACK SCSConnectionCheck SCSGPSSensorData scs ActorAddress Add code for serialization of position String SCS SCSList scsList ArrayList SCSPCSDown SCSPCSFailed mySCSS Add code for serialization of ActorAddress mySCSS SCSRegistered yourMS Add code for serialization of ActorAddress yourMS SCSSensorStatusRestored scsList ArrayList scs ActorAddress SCSSetupParameters yourCSS Add code for serialization of ActorAddress yourCSS SetupParameters UpdateCSCommLinkStatus csname
150. ing more sensors and agents It should also be noted that no functionality for removing node actors has been implemented this would be a natural extension to a fully functional system enabling nodes to be removed and re installed in different settings The setup of the ActorRouter default gateways can also be discussed especially in light of the functionality currently offered A dedicated node running an ActorRouter entity functioning as a default gateway for all nodes provides a single point of interaction for the entire system ensuring that all actors can be located This solution does also present several drawbacks This node can become a bottleneck it is a single point of failure and all registering actors must present publicly accessible addresses The design and implementation has been done to provide a demonstrator for this system Being a demonstrator it also provides limited functionality This aside the implemented demonstrator will be able to provide the services required from a single sea cage with a GPS receiver and a GPRS modem 10 3 New features and extensions As presented throughout this thesis the current design and implementation have been made for creating a demonstrator of the system The design has also looked ahead and attempted to provide the building blocks for future extensions to the degree of 118 SCG A Distributed Sensor Management Network in ActorFrame potential mobile grid computing eleme
151. inux Since only one of the available machines has WLAN capabilites Ethernet connections will provide communication This is transparent for the nodes compared to a WLAN connection 9 1 Incorporated hardware In this section the equipment used to demonstrate and test the SCG system application is presented The system is comprised of three computers each simulating a node of the system In addition a GPS sensor and GPRS modem have been attached to the machine representing the SCS node 9 1 1 Node computers The computer running the MSAgent actor is a Netshop 259IEN laptop computer It has a 2 0 GHz Pentium M processor with 1 GB of memory and is running Windows XP It is shown in Figure 9 1 Figure 9 1 The MS node computer This computer also runs the MySQL database and the web server both are described later 90 SCG A Distributed Sensor Management Network in ActorFrame The computer simulating the CS node and running the CSAgent actor is a Compaq Deskpro with a 733 MHz Pentium III processor with 384 MB of memory running the Linux based Ubuntu 6 06 operating system It is shown in Figure 9 2 Figure 9 2 The CS node computer The SCS node with the SCSAgent is an Advantech ARK 3381 50 embedded box computer with a 598 MHz Intel Celeron processor and 480 MB of memory running Windows XP This is the type of computer which might actually be deployed on a sea cage It is shown in Figure 9 3 Figure
152. ion self configuration node connection and sensor data retrieval to the context manager developed in 11 allowing the division of tasks between specialized and optimized entities In addition to the basic scenarios this thesis and demonstrator have been based on there are other services that the SCG domain may require support for One example of this is the delivery of a camera feed to the mainland for visual surveillance of the fish stock The transport of streaming video data is not a task for ActorFrame but it could perhaps be utilized in discovering and providing access to such functionality The application could provide the necessary data for an external application to setup the data stream New features and extensions have already been proposed for the ActorFrame framework and Ramses in section 10 1 and are not repeated here 10 4 Future work The demonstrator provided here is simply the first step in realizing an SCG system in the ActorFrame framework If the system is not further implemented in ActorFrame there should be some principles that may apply which have been uncovered here Still there are still many areas of future work applicable to what has been presented here These topics vary over a vast majority of areas The new features and extensions proposed in previous section can all be considered as possible areas of future work and consideration There are also many other topics springing out from the SCG system which cou
153. ipulating the database values and is created by the DBEdgeSM class upon initiation These methods are aimed at making database interaction as simple as possible seen from the ActorFrame application The methods provided are shown in the simple class diagram in Figure 9 10 method parameters have been left out SQLInterface 0 ERI updateSCSCommLinkECS updateSCSCommLinkPCS updateCSCommLinkeFCS setCsStatusYellow setCsStatusRed setScsStatusYellow setScsSTatusRed setScsStatusGreen updateSCSPosition updateCSPosition checkSCSStatus checkSCSCommLink Figure 9 10 The class diagram for the DBEdgeSM Not all of the methods provided have been used in this demonstration The full code of the SOLInterface is available in Appendix D 9 2 4 SMSEdge The SMSEdge actor provides an interface towards an SMS server residing in the PATS lab of Telenor R amp D Trondheim The connection towards this SMS server has been created through the use of Web Services using the SOAP protocol and a client generated from a WSDL file created by Telenor 63 An SMS class using the generated web service client which allows access to these services has been provided by Telenor R amp D This SMS class provides the three methods necessary for setting a receiver setting a message and sending an SMS These are shown in the class diagram in Figure 9 11 99 SCG A Distributed Sensor Management Network in ActorFra
154. iscussed It is good practice to branch on signal and not a signal parameter value but in the case of incorporating new sensors in the SCG system using sensor neutral signals can be an advantage By adding the new sensor data to a pre existing String of data this data can easily piggyback through the system back to the MSAgent In such a scenario one does not have to implement a new signal throughout the system and state machines In the demonstrator with only one sensor a sensor specific signal has been implemented the GPSSensorData signal This is an area applicable for further discussion and distinctions between the sensor data in the system may be necessary The SensorControlAgent actor regularly queries the sensors for data both for threshold value checks as well as for logging purposes The sequence diagram for this 15 shown in Figure 8 36 75 SCG A Distributed Sensor Management Network in ActorFrame sd Communication between a sensor and SCS se SensorEdge sca SensorControlAgent sda SensorDataAgent scsca SCSControlAgent loop SensorU pdateTimer 1 RetrieveSensorData T 1 SensorUpdate SensorDataFormat 1 T T 1 1 Proactive sensor polling Hybrid sensor polling i SET NOW time SensorUpdateTimer
155. istributed Sensor Management Network in ActorFrame AddM MsrToDbe etSensorUpdate AddCSToDB AddSensorToDB PosAlertForSCS SCSPCSFailed MsrToCsm MsrToDbe MsrToDbe PosAlertFor a GPSSensorData ResetDefaultGPSPosition ensorStatusRestored MsrToDbe SPSSensorData PSSensorData via MsrToDbe PCSRestored estored via MsrToDbe MsrToDbe gt UpdeteFinished SOS ensorData vi MsrToDbe MsrToDbe MSControlAgent The port MscaToMsr is connected to the MSRouter actor AddSensorToDB 167 SCG A Distributed Sensor Management Network in ActorFrame CSManager The port CsmToMsr is connected to the MSRouter actor e idle UpdateCSList gt AddCSToDB Dd SensorToDB PosAlertForSCs 0 CSList AddCSToDB CsmToMsr X PT SCSPCSFailed SetupParameters gt idle etSensorUpdate GetSensorUpdate ensorData CsmToMsr ECaRestored gt GPSSensorData CsmToMsr false true GetSensorUpdate gt pollingCS idle CSSession The variables myCS and myCSM are ActorAddresses for the CSSession s CS node CSRouter and CSManager etupParameters etupParameters TG myCS pSCSRCSEalled
156. l machines running a JVM Java Virtual Machine Unfortunately in the SCG system a certain level of interaction with the operating system 15 necessary and it is therefore important to identify the operating system the application is running on Java can not directly interact with the operating system this requires the use of wrappers and JNT and can be a complicated process Java Native Interface This provides an interface between Java and the native Windows code 96 SCG A Distributed Sensor Management Network in ActorFrame The OSAPIAgent immediately checks upon initiation which type of platform it is running on This is simply done through the getProperty method of System as shown below The result of the getProperty method causes the generation of a RoleRequestMsg signal specifying the required OSAPIEdge This system currently only supports Windows XP through the WindowsAPIEdge actor Once initiated the WindowsAPIEdge handles all operating system specific interaction In the SCG system implemented here it has only two tasks initiating and terminating the reserve communication link The reserve communication link is initiated by nitECS signal which triggers the following code The connection is disengaged when the PCSRestored signal is received by the WindowsAPIEdge with The waitFor method ensures that the connection has been initiated or terminated before confirmation is sent to the adhering S
157. l or connection status initiate GPRS upon WLAN disconnection There should be implemented several actors for several operating systems a minimum for Linux and Windows For this system only a WindowsAPIEdge has been implemented but other operating system edges can easily be added The inner structure is shown in Figure 8 12 OSAPIAgent lt lt Actor gt gt WindowsAPIEdge Figure 8 12 The OSAPIAgent actor design The WindowsAPIEdge actor is directly available to the SCSRouter through a delegation port The actor for the specific operating system will always connect to this port SCSRouter actor 55 SCG A Distributed Sensor Management Network in ActorFrame The SCSRouter actor handles addressing issues for the actors of the SCSAgent actor In addition to handling local addressing between actors not connected by ports it also handles the sending and receiving of messages to and from the other distributed actors of the system This provides a level of layering between the actors of the SCS node and those on the CS node MS node and eventually the other SCS nodes The advantages of having a single point of interaction with the rest of the system are many First and foremost the use of a designated actor to handle distributed communication enables an easier control of link failures The SCSRouter actor uses timers for distributed communication and can easily discover lacking responses and hopefully take care of thi
158. ld provide a basis for further study This is both in the SCG domain itself and adjourning areas discussed in this thesis 121 SCG A Distributed Sensor Management Network in ActorFrame A full economic study of all aspects of the SCG domain from the hardware incorporated via communication links to sensors and software should be conducted This requires a basis for the characteristics of the equipment needed which again requires defining the needs of the system An example of this is determining the bandwidth requirements of the SCG system elements both for primary operation modus and for the redundant communication links Specifying the resource needs of the node hardware is another example These are both are areas of further study With distributed nodes connected through an unstable network connection there are cases in which the nodes will be cut of from each other Both the nodes themselves and the communication links may fail This can present many challenges How does an actor handle a missing signal due to a communication failure This has already been considered partially in this thesis both in reducing the number of directly inter communicating actors but also regarding link failure detection on signals expecting responses Still this has not been implemented and tested and are therefore simply suggestions In addition the case of synchronizing data and states when previously disconnected nodes regain contact Ensuri
159. lems related to their use Among the factors that can be considered problematic for sea cages are currents the spread of disease in a confined area vulnerability to drifting objects fouling and wastes from fish and feed exposure to weather and climate ice light predators scavengers etc They also occupy large areas of attractive coastal areas may alter the behaviour of local animals and can contribute to the spreading of sea lice 2 4 Aquaculture in the future As previously mentioned there are several changes occurring within the aquaculture industry Previously when production was relatively low the rearing facilities were few and far between With an increase of production these facilities increased in both size and numbers moving from inland facilities to coastal This represents a challenge for the environments currently supporting aquaculture instalments Not only will there not be enough room in calm coastal waters but the pressure on the local environment will be large depleting the conditions for not only the reared fish but also other species dependent on the local conditions Pollution and waste from fish farms have already been mentioned Larger scale aquaculture production may also aid to relieve pressure on over fished populations species 1 e cod With offshore production facilities these factors can be relieved due to stronger currents deeper waters and space allowing for problems experienced in coastal areas to be natu
160. lity is beyond the scope of this thesis but is an interesting area to develop further 8 3 Generic design of the system Here a generic design of the system is presented and described The implementation will use parts of this in addition to specialized actors of the generic concepts presented here An example of this will be given for the SensorAgent actor presented in the next section The actors and their inner actors are shown and functionality is presented with sequence and communication diagrams The bases for the design are the elements identified in the previous chapter combined with the functional requirements domain description and sensor network and grid computing influences The design process has been an iterative process with more than one change applied during implementation Subsequently the designs presented have evolved compared to the original drawings Several of the designs presented include elements which have not been implemented and are shown only to illustrate further areas of function for the SCG system These functions are considered beyond the scope of this thesis or unnecessary for the implementation of the demonstrator Where the design differs from implementation the actor name is surrounded by parenthesis and it is commented in the particular section Ports and connectors have not been used between distributed actors due to the lack of support for this in ActorRouter As mentioned in section 7 2 2 1
161. lly initiated from the CS The intervals between communications have to be set according to the sensor data required and the capacity available on each SCS node Generally communication between the CS and SCS is generated on three occasions The first is the aforementioned alarm situation the second is the regular polling conducted by the CS based on a timer interval third is on request from the MS Under normal communications only the regular polling from the CSAgent has been implemented The sequence diagram for when a CS node retrieves sensor data from its SCS nodes is shown in Figure 8 32 72 SCG A Distributed Sensor Management Network in ActorFrame sd CS updating SCS sensor data csca CSControlAgent scsr SCSRouter scsca SCSControlAgent r 1 rSensorUpdateTimer e The CS requests sensor data from its SCS UpdateCompleted 1 SET NOW time SensorUpdateTimer Figure 8 32 The sequence diagram for a CS updating its sensor data As with the MSControlAgent the CSControlAgent sensor data retrieval procedure is timer initiated This timer is set for the first time when the CS is alerted of a sensor connected to a SCS node When all the SCS nodes have reported their sensor data the CSControlA gent is notified through UpdateCompleted signal When the Sensor UpdateTimer timer has been invoked the CSControlAgent generates a request to its SCSManager to retrieve the sensor data from all SC
162. me Figure 9 11 The class diagram for SMSEdgeSM The SMSEdgeSM class instantiates a new SMS class upon initiation and uses this to generate SMS alerts when asked to by the system The edge currently offers two types of SMS one for position alerts and one for communication link failure The message sent in an SMS contains SCS node that generated the warning and type of alert it is The sent SMS are shown in Figure 9 12 Figure 9 12 The SMS warnings generated for GPS position deviation left and link failure right The message recipients and text have been specified by the SMSEdge actor and are extended with the actor generating the alert and in the case of a position alert the current position of the sea cage 9 2 5 AdminEdge A simple AdminEdge actor has been implemented to provide some interaction with the system for testing and simulation purposes The function it provides is a GUI which allows for the user to send a message to re instantiate the PCS connection and reset the default GPS position This simple GUI is shown in Figure 9 13 amp Reset GPS Reestablish CommLink Figure 9 13 The AdminGUI 100 SCG A Distributed Sensor Management Netwo
163. ment and monitoring of offshore installations in the aquaculture environment This system is dependent on wireless technologies to provide the connections necessary Due to changing and varying needs in the industry the possibility of moving such installations from the safe harbours of fjords and near coastal areas to offshore locations is currently being reviewed The advantages of relocating fish farm installations offshore are many Among these one can mention factors such as larger scale production protection of vulnerable coastal areas freeing up over populated fjords and the ability to install fish farms in previously inaccessible areas This project also focuses on making such technology as cheap and accessible as possible allowing it to be utilized on smaller installations The technology and design decisions keep this in mind maintaining a focus on non proprietary hardware and open source software Low introduction costs are hoped to make the technology easily accessible and enable many potential actors in the market What kinds of communication technology and system design principles are necessary to meet the requirements needed for such a venture A heightened awareness to the possibilities introduced by new technology could improve both production and add value and services to the entire value chain giving an edge in a competitive market Through the coordinated use of sensors and sensor data production can be optimized and prod
164. ment Network in ActorFrame If the frequency of interactions between the distributed actors is rare a heartbeat or hello signal could be implemented to regularly check communication link status If the frequency of signal interaction is sufficient then such a signal may not be necessary it would simply drain power and bandwidth As shown under the normal operations section the queries are often issued from the top down in this system This means that the CS requests a report periodically from its SCS nodes instead of the SCS nodes themselves initiating reports In exception cases however the SCS can send alarm messages to the MS or CS A timer is set for every interaction by the initiating side The assumption is made that the management station is under surveillance and has backup routines for failure The possibility that the MS fails should otherwise be considered In the implementation for the demonstrator only the case of a failed PCS link discovered by the SCS has been implemented Subsequently no timers on messages are set except for those generated periodically by the SCSAgent to check PCS status The remaining sequence diagrams are suggested solutions and have neither been implemented nor tested but their patterns are very similar to the one used in the demonstrator They may function as a starting point for considering such functionality 8 4 3 1 Failed PCS between SCS and CS In the event of a failure between a SCS and it
165. mework can take advantage of the Service Discovery protocol native to Bluetooth Besides that there are many further unexplored areas in the SCG domain Extending functionality to provide further services and implementing the unimplemented design proposals presented here are just a few of them The handling of the SCS nodes during ECS operation here simply handled by the CSSession actor could be further discussed and the solution of a ReserveSCSSession as an inner actor of the CSSession as presented in section 8 3 3 could be considered Also how to assign groups of rescue and service teams to each CS node and its SCS nodes is another area that should be further explored The automatic assigning of rescue and service teams upon a new node connection would extend the self configuration aspect of the system even further The handling of sensor data and in what format it should be kept in is also an area for discussion In this system the position data has been handled by a position specific object locally in the SCS node and is later reported in as a simple String This depletes the original sensor reading when sent beyond the SCS node Sending the position data in the original LatLng class or any other GPS oriented object allows for the CS node or MS node to perform operations on the data An example is the case of detecting if a sea cage is drifting If this were a complex operation to large for the SCS node computer it should be sent to the
166. modelling is the play annotation incorporated A play can be compared to a service provided by actors playing roles to achieve a performance These collaborations last as long as the service is needed As with a play an actor can play several roles and be a part of several plays This is shown in Figure 7 4 o T Play2 MOn Actori Actor2 Actor3 Actors Actors Play3 Figure 7 4 The elements of a play 42 To set up a service the RoleRequest protocol provided by the framework is used This consists of a RoleRequest message sent to the actor incorporating the role required This can either be the actor itself or from one of its inner actors If the role can be performed a RoleConfirm message is sent to the originator of the RoleRequest message and the role can be used The protocol is shown in Figure 7 5 Requested Actor ActorSM 7 1 Requestirole 2 Playirole E 3 Confirm role x Requesting lt invoked Actor Actor Figure 7 5 The RoleRequest protocol 42 When a role is no longer necessary in a service or the service itself is discontinued a RoleReleaseMsg signal can be issued to the actors participating The RoleReleaseMsg message removes not only the actor which receives the signal but any other actors who have been request by that actor and so on The response to a RoleReleaseMsg signal is RoleRemovedMsg si
167. more complex documentation and testing is part of modelling process The modularity of the design provides freedom for distribution and reuse Providing a peer2peer relationship between the system entities allows for more flexible functionality In the demonstrator for instance it allows for alarms and alerts to be generated by many parties in addition to allowing the surveillance of communication links to be controlled by both sides It could be said however that the system design implemented a certain level of client server structure amongst peer2peer nodes providing easier more controllable and more understandable interactions between nodes This is most apparent in the hierarchy used and the sensor data reporting and link status controlling functions Beyond that the possible 111 SCG A Distributed Sensor Management Network in ActorFrame grid computing and sensor web based functionality can possibly be integrated into the existing architecture The design and implementation also allow for the distribution of actors to separate nodes which can aid both fault tolerance and enable load sharing on potential bottle neck actors and nodes There are however some extensions to the framework that could further improve the support it could give to the domain in question distributed systems deployed over heterogeneous and changing networks technologies with dynamic node presence The wired fixed communication domain of ActorF
168. n in turn adds the new CS node to the list of current CS nodes by sending the UpdateCSList signal to its parent the CSManager actor The CSManager actor updates its list of CS nodes and sends the updated list of CS nodes to all of its children inner actor CSSessions not shown CSSession then forwards the list to their designated 7 Signal and message are used as synonyms in this thesis 64 SCG A Distributed Sensor Management Network in ActorFrame CSAgent actor more precisely the CSRouter actor which handles all communication with higher placed nodes in the SCG hierarchy Finally and if necessary a set of basic parameters are sent out to the CSRouter which forwards these to CSControlAgent actor not shown This allows for basic parameter setting directly and automatically from the MS if the default values aboard the current CS are obsolete or unavailable There are no such parameters included in the demonstrator To clearly see the messages being passed between the SCG nodes a high level communication diagram is shown in Figure 8 23 comm A new CS registers with MS Database 2 3 AddCSToDB 2 RegisterCS 2 2 CSRegistered 2 3 CSSetupParameters x CSAgent MSAgent 2 1 CSList 1 RoleRequestMsg gt 1 1 RoleConfMsg 2 3 CSList CSAgents CSAgent registered Figu
169. n regarded and that is why the amount of actors collaborating directly has sought to be reduced through a hierarchical and separated design In addition these tests were to test functionality under controlled circumstances and are no guarantee for proper function when used outside this environment They have inevitably failed for the first few iterations of development before all issues were resolved It is also through this process that logical inconsistency and other unexpected or unforeseen elements were discovered and consequently attempted solved In the following section the successful results are displayed and elements that were not solved are commented Largely the tests correspond to the sequence and communication diagrams presented in section 8 4 The tests were conducted by first administering them on the SCG system simulated in an outer actor named the SCGSystem actor The design of this actor is shown in Figure 9 20 106 SCG A Distributed Sensor Management Network in ActorFrame SCGSystem lt lt Actor gt gt 0 10 0 5 SCSAgent CSAgent MSAgent Figure 9 20 The SCGSystem actor design This allowed for testing all the elements on a local system before distributing the agents on their respective nodes It also allowed for testing of several CSAgents and SCSAgents at once which provided the basis for considering the distribution of addresses among actors After the test was passed on the simulated SCG sys
170. n Norway 26 This service has just recently been opened for public and commercial use and provides services such as mobile and portable broadband to remote districts where such services have previously been unavailable Due to the lower radio frequency used by this technology the coverage 15 equal to or greater than other comparable technologies and the data rate 1s larger The coverage provided with the portable broadband modem 15 shown in Figure 6 2 and provides a theoretical maximum capacity of up towards 2 Mbit s 1 3 Figure 6 2 Coverage map for CDMA450 for portable broadband modem 27 Although the initial data rate is larger than for instance GPRS EDGE the capacity is reduced when there are many simultaneous users connected to the same access point As with GPRS CDMA450 uses licensed frequencies and require a vendor delivered infrastructure In addition the current payment model only allows up to 2GB of data transmissions per month 26 CDMA450 could primarily be considered for the ECS and FCS but with the data rate offered it could also function as a PCS or MCS This is dependent on the amount of 24 SCG A Distributed Sensor Management Network in ActorFrame data transferred on the communication link an amount currently difficult to predict without further study 6 3 WLAN WLAN is an abbreviation for Wireless Local Area Network and is the more common term for the 802 11x
171. n section 8 4 2 and corresponds to the functional requirement five The results are shown in Table B 2 Table B 2 Test of the sensor update functionality Function tested Expected behaviour Result Simulated Distributed 1 The a Upon a timer initiative a OK OK GPSControlAgent ReqGPSPosition is sent to the requests sensor GPSSensorEdge data from b The GPSSensorEdge retrieves OK OK GPSSensorEdge position data from the sensor and puts this in the GPSPositionUpdate signal c The GPSControlAgent receives OK OK the position update and can compares it to the default position e A new timer interval is OK OK initiated 2 The a A GetSensorUpdate is sent to OK OK SCSControlAgent the SCSManager from the requests a sensor SCSControlA gent when the update from the timer is set off GPSControlAgent b The SCSManager sends a OK OK GetSensor Update to the GPSControlAgent c A GPSSensorData signal with OK OK the position is returned to the SCSControlA gent d A new timer is initiated OK OK 3 The a A GetSensorUpdate signal is OK OK CSControlAgent sent from the CSControlAgent requests a sensor when the timer is invoked 137 SCG A Distributed Sensor Management Network in ActorFrame update from the b The SCSManager consequently OK OK SCSControlAgent queries all SCS for sensor data one c The SCSRouter sends the OK OK request to the SCSControlA gent d The SCSContr
172. ncy for the SCG system The demonstrator has shown that ActorFrame can provide the support for the system functionality The basic functionality required was provided in an easy and clear manner The keywords presented after the domain description and scenario in section 3 1 1 were self configuration ease of use autonomy sensor handling self monitoring and fault tolerance All of these were provided using the ActorFrame framework The MS node was aware of all of its CS nodes and their capabilities the CS nodes were aware of all other CS nodes in addition to their own SCS nodes and their capabilities SCS nodes were aware of all other SCS nodes under the same CS node Interaction with non ActorFrame elements such as the SMS server and database were relatively easily integrated into the system through Edge actors In addition ActorFrame provides modelling concepts and designs that are easily verified validated distributed tested and extendable The last point especially provides flexibility and adaptability necessary to handle new demands and technologies when these arise But as shown through this thesis some elements of the systems functionality had to be handled specifically through application and system design due to shortcomings of the ActorFrame framework Compared to the proposed use of client server architecture with Web Services from 1 2 there are advantages gained through use of ActorFrame Although the system may be seen as
173. ng the COM port to which the GPS sensor is connected to The LoggingServer class diagram is shown in Figure 9 6 CommPortldentifier GPSHandler gpsUpdate in data string Figure 9 6 The class diagram for LoggingServer http www gnu org licenses lgpl html 94 SCG A Distributed Sensor Management Network in ActorFrame The LoggingServer creates a connection to the specified COM port identified by CommPortlIdentifier class When the COM port is opened SerialPort connection is created The JnputStream class then represents the information received through the SerialPort connection This nputStream is then read and presents the NMEA messages from the GPS receiver When a full NMEA message has been received the LoggingServer class calls the gpsUpdate method of GPSHandler with NMEA String as parameter The method initiate opens a new InputStream to retrieve the latest reading from the GPS receiver and is called from the GPSHandler class The code of the LoggingServer class is presented in Appendix F 9 2 1 2 Parsing and interpreting GPS data When a connection to the GPS sensor has been established the data received from it must be interpreted To enable this NMEA parser has been included The classes NMEA and GPSInfo are from the open source JavaGPS package 58 and LatLng is from the JCoord package available under the gnu GPL license 59 To provide interaction with the LoggingServer an
174. ng the propagation of correct and up to data information must also be handled In the implemented demonstrator this is relatively simple as no log is kept over the GPS positions of the sea cage But if the CSAgent is to keep an updated log of sensor values in periods in which it has no connection with the SCS node there may arise inconsistencies As mentioned in the previous section further investigating and exploring the grid computing potentials of the SCG system are of interest Many mobile grid computing elements can be studied such as task scheduling status distribution energy awareness network awareness and consistency management With the system design as it is all possible sensors must have defined SensorA gents capable of handling their sensor input This implies that if a new sensor is introduced in the aquaculture domain all SCS and CS nodes must be reinstated with a new and updated SCG system application This can be quite a large task especially when the system is well functioning before update It could be interesting to see if new actor specifications could be implemented and installed during run time of the current actors Such dynamic class configuration could greatly simplify the introduction of new sensors into the system But the introduction of a new actor could quickly affect the whole system in several ways If new signals variables and parameters must be introduced for the new SensorAgent this will imply updating sever
175. nnection con null Statement stmt null int affected 0 try String url Class forName com mysql jdbc Driver newInstance con DriverManager getConnection url user komtek stmt con createStatement affected stmt executeUpdate UPDATE CS SET commlinkid 4 where csname csname ir 2471 System out println The CS comm status has been updated else System out println The CS comm status has not been updated catch Exception System out printin Problem e toString finally seme iry 4 stmt close catch Exception Eystem out prriHblin ojtostrbing stmt nuli IE try con close 148 SCG A Distributed Sensor Management Network in ActorFrame catch Exception e System out prinkiln e null public void setCsStatusYellow String csname throws Exception Connection con null Statement stmt null int affected 0 try String url scgdb Class forName com mysql jdbc Driver newInstance con DriverManager getConnection url user komtek stmt con createStatement affected stmt executeUpdate UPDATE CS SET statusid 2 where csname csname System out println The CS status has gone to y
176. nnot be the same In the event of a primary link failure the system must detect this and adjust the data distributed to the available communication technology An example of this is if the ECS is the current communication link In this case all other communication links are down implying an urgent need for repairs in the system In addition only critical information should be broadcast over this backup link for instance large deviations in the position of the sea cage Such deviations may indicate a possible moorage breaking 3 1 1 Scenario To form a basis for the system to be developed and to base some functional requirements and design objectives on a simple scenario has been defined These are based on the domains descriptions provided in 1 and have been supplemented with the initial desired setup of such a system With the new low cost SCG system Nils Nilsen has decided to invest his life savings into a fish farm of his own In his remote coastal community times are hard and jobs even harder to come by FishFarmAS already provide the MS node necessary for superior administration of the system This means that he only needs to invest in the This element could also have been provided by the owner himself It is just to show that automatic sevice configuration allows for many actors to be part of the SCG domain For the remainder of this thesis the physical entity of a system element will be referred to by its abbreviation sometime
177. nodes SCSSession and CSSession 160 SCG A Distributed Sensor Management Network in ActorFrame RoleRequestMsg gt waitForRoleConf gt RoleConfMsgi connectionUpdateTimer 55 SSetupParameters BpnnectionCheckTimert etupParameters via V do ConnectionUpdate bie ScstToScsa idle mySCSS TO myCSS egister nfo ConnectionUpdateToMS DsetSensorUpdate ide mySCSS 1 I idle pe SCSConnectionACK onnectioUpdateRep waitForScss eer 5 i idle SCSRegistered D Nes 0 idle NewSensor mySCS SCSList GPSSensorData ensorData mySCSS ecsinitiated PositionAlert TnitECS PosAleriF orSCS PositionAlert GPSSensorData PCSRestored ScsrToOsapia mySCSS wnt vi OSAlel ensorData estore S myCSS gt myCSS ScsrToScsa gt ScsrToScsa connectionTimer ecsinitiated PCSRestored ecsinitiated initiatingECS ecslnitiated SCSControlAgent The ports used by the SCSControlAgent are ScscaToScsr which is connected to the SCSRouter and ScscaToSm which is connected to the SensorManager GSSetupParameters NewSensor PositionAlert SPSSensorDatal GetSensorUpdate ScscaToScsr SescaToScsr SescaToScsr sensorUpdateTimer PCSDown
178. ns the generated no ntnu item master2006 jcoord 1 0 zip code for the CSAgent no ntnu item master2006 ext GPSHandler RXTXcomm jar actor no ntnu item master2006 ext mySQLHandler no ntnu item master2006 ext simpleAdminG UI no ntnu item master2006 ext smsHandler se ericsson eto norarc actorframe scsagent Contains the generated no ntnu item master2006 jcoord 1 0 zip code for the SCSAgent no ntnu item master2006 ext GPSHandler RXTXcomm jar actor no ntnu item master2006 ext mySQLHandler no ntnu item master2006 ext simpleAdminG UI no ntnu item master2006 ext smsHandler se ericsson eto norarc actorframe simulation Contains the generated no ntnu item master2006 jcoord 1 0 zip standalone application simulation no ntnu item master2006 ext GPSHandler no ntnu item master2006 ext mySQLHandler no ntnu item master2006 ext simpleAdminG UI no ntnu item master2006 ext smsHandler se ericsson eto norarc actorframe RXTXcomm jar All JARs are provided in systemjars zip file part of Appendix I In addition to the mentioned items the projects which use the GPSSensorEdge must add the files rxtxParallel dll and rxtxSerial dll to the same folder These are used to interact with the Windows operating system These are also part of the systemjars zip file 5 Initiate the database as described in Appendix 6 Download and run a web server Place the scgstatus jsp file in the webfiles folder of the web server This file is avail
179. nt of advanced hybrid and personalized services without sacrificing the quality In other words the goal is to be able to design develop and offer advanced hybrid services in the shortest time possible With hybrid services the paper refers to services provided across different networks by different service providers 45 This is done by focusing on the application domain of the service The generic application domains considered in ServiceFrame are shown in Figure 7 10 36 SCG A Distributed Sensor Management Network in ActorFrame EndUsers Community present at JserTerminal Appliance ServiceEnablers Clients Application Business logic Resources Figure 7 10 The application domain incorporated by ServiceFrame 45 The key design principles used for ServiceFrame are conceptual abstraction environment mirroring role modelling service centred architecture and the use reuse of frameworks and patterns For more information on ServiceFrame see 45 The SCG system may not appear to be in the domain of ServiceFrame at first glance How can a sensor administration and retrieval system fit in here Who are the users Who are the communities What are the terminals In a sense all of the above are present in the SCG system The users are the nodes themselves in addition to the human users of the system The communities can be all similar nodes such as all SCS and CS nodes local or glob
180. nts The road to actual implementations of such functionality is long and complex with many additional issues to consider providing the basis for many possible theses An interesting basis scenario could be the introduction of new actors to the SCG domain actors which are mobile in nature The SCG domain can be extended to contain many new outside parties interested in both the data generated and in direct interaction with the system An example of this is if the fish collection boat which harvests the biomass produced in the sea cage is handled by an outside party This party is then to gain access directly to the current SCS preferably automatically and seamlessly One step has been taken by proposing a Mobile TerminalAgent actor residing on each distributed node The intention for this actor is to provide support for roaming actors wishing to interact with this particular SCSAgent An assumption has been made of no more than one mobile terminal per agent per time therefore a form of UserAgent has not been considered Not to say that a type of UserAgent may not be necessary This MobileTerminalAgent will provide access to the entire SCG system through the SCSAgents knowledge of the domain it is in in addition to knowing the other nodes capabilities and capacity The nature of the actors wishing to interact could be outside the traditionally considered actors and these actors can wish interaction with the SCG system without ever having been consi
181. o provide self contained and self configuring remote sensing and control of offshore sea cage installations In addition the design has been inspired by areas such as sensor networks webs and grid computing providing some simple building blocks and principles for further development The steady increase in wireless long range high capacity communication technologies make it more and more plausible to implement many of the visions of the SCG system The amount of possible technologies has grown to the point where not only one but several links can be established from each node It should be noted that some of these technologies have only just been released for commercial interests and there is still some doubt to how well they will perform beyond the theoretical domain Still there currently exist technologies that will suffice to the basic needs of the SCG system The abundance of communication links and technologies also challenge former network transparency issues making the network more visible to applications than before A demonstration system has been designed and implemented with the ActorFrame framework aided by the model driven design tool Ramses This has aided in keeping the distance from design to implementation very short The demonstration system has provided the possibility to prove and test basic principles and logic The results have been encouraging Support for automatic system set up sensor reporting and alarms genera
182. oduction is of great interest for the industries and the use of sensor data and efficient exploitation of them could optimize breeding conditions 2 3 Cage techniques The initial goal of holding fish was to keep captured stock alive until it could be sold at the market This was probably done through simple cages and fish traps The actual culture of fish where fish were kept for longer periods of time and gained weight have references back to the Han dynasty of China almost 2200 years ago 3 These cages consisted only of cloth with bamboo sticks for support Since then several types of aquaculture facilities have been developed and defined The most common types are Enclosure is where the shoreline is the natural boundary on all sides but one is an enclosure where all sides of the structure are man made except the bottom Cage is an enclosure where all sides of the structure are man made a floating device The most used in the context served in Norway and in offshore locations are cages There are several sub categories of cages all with different capabilities In Figure 2 2 a rigid sea cage is shown Rigid sea cages are as the name implies a rigid construction This gives great platform stability and easy access on onboard walkways SCG A Distributed Sensor Management Network in ActorFrame for fish farm personnel Unfortunately such construction can not withstand rough conditions due to their stif
183. of power consumption and battery levels 24 In other words applications must be terminal aware network connection aware and power aware This has many parallels to the conditions the SCG system will experience The SCS nodes have limited resources both processing and power wise the communication links of the system can be of several types and characteristics disconnections will probably occur mobile nodes can be introduced and there can be different operating systems and different computers implemented on nodes All these elements must be considered and attended to meaning that the system must be aware and take advantage of them 22 SCG A Distributed Sensor Management Network in ActorFrame 6 Communication technologies In this chapter a variety of the possible communication technologies for enabling communication among the nodes in the system are presented UMTS is not considered as it does not have and will not likely achieve the coverage necessary to offer the connections required Although EDGE only requires an update to current base stations and thus in theory has the same potential coverage as GPRS current coverage is still poor and it is therefore not included GPRS WLAN and WiMax are presented in 1 and 2 but satellite communication CDMA450 and VHF Data are not To set these technologies up against each other all of them are presented here Bluetooth and ZigBee are also presented in this section
184. olAgent csm CSManager CSSession UpdateSensorData STOP SensorUpdateTimer UpdateSensorData C STOP SensorUpdateTimer lez turc ced SensorUpdateTimer FER 3 GetSensorUpdate loop 1 csList size GetSensorUpdate ref Collecting CS information CSSensorDataUpdate sensorData CSSensorUpdate sensorData 1 1 1 1 UpdateCompleted ee SET NOW time SensorUpdateTimer 1 1 f 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 I Figure 8 29 sequence diagram for the collection of sensor data from the MS node When the SensorDataUpdate signal is received the signal is sent both to the MSControlAgent actor and to the DBEdge actor this is done automatically by the MSRouter actor The DBEdge actor inserts the sensor data into the database When all updates are finished the MSControlAgent actor is notified of this through t
185. olAgent returns OK OK the latest position in the GPSSensorUpdate signal e The CSControlAgent receives OK OK the latest position and stores this f When the UpdateFinished OK OK signal is received a new timer is set 4 The a A GetSensorUpdate signal is OK OK MSControlAgent sent from the CSControlAgent requests a sensor when the timer is invoked update from the b The CSManager sends the OK OK CSControlAgent GetSensorUpdate to the CSSessions one c The CSControlAgent and the OK OK DBEdge receive the GPSSensorUpdate signal d The DBEdge updates OK OK database and the web interface registers the change e The CSManager sends the OK OK UpdateFinished signal when all CS have sent sensor updates f The SensorUpdate timer is OK OK reset c Testing sensor and PCS failure alarms In the following table the results of the tests for sensor deviation and PCS failure are shown For the simulated version the PCS failure was initiated by discontinuing the replies of the SCSConnectionCheck messages and for the distributed test the Ethernet cable was pulled out The functional requirements corresponding to this functionality are three four and six The results are shown in Table B 3 Table B 3 Test of the sensor deviation and PCS failure detection and alarms Function Expected behaviour Result tested Simulated Distributed 1 The GPS a The positi
186. on java lang String myTA se ericsson eto norarc ejbframe ActorAddress taiRouteAgent myUA se ericsson eto norarc ejbframe ActorAddress myVC se ericsson eto norarc ejbframe Actor ddress routelnfo no ntnu item project2005 route Route 8 25 region idle waitForRouteAgent waitForRouteRequest waitForRoutes waitForVirtualCorridor pa PositionAgent 2 idle waitForRouteAgent toPositionEdge waitForRouteAgent gt waitForVirtualCorridor idle gt waitForRoutes 2 waitForRoutes gt idle P waitForlirtualCorridor gt idle 9 waitForlirtualCorridor gt waitForVirtualCorridor 93 ide gt waitForRoutes VirtualCorridor 0 1 pe PositionEdge gt toRouteAgent WI toUserPosition UserAgent UserPosition VirtualCorridor item project2005 quidancesystemandterminal SimulatedSystem no ntnu item project2005 signals quidancesystem E se ericsson eto norarc actorframe 2 0 0 Inner Parts Structure Problems 22 Javadoc Declaration Console Error Log pren Figure 7 12 Screenshot of the Ramses model view in Eclipse For more information on the Ramses system development tool see 47 38 SCG A Distributed Sensor Management Network in ActorFrame 8 Design of the
187. on deviation is OK OK receiver is discovered by the 138 5 SCG A Distributed Sensor Management Network in ActorFrame moved beyond the boundaries GPSControlA gent b A PositionAlert signal 15 sent OK OK The SCSAgent CSAgent and MSAgent are notified OK OK d An alarm is issued by the SMSEdge OK OK The database is updated with new position and SCS status is set to yellow OK OK 2 The PCS is disconnected The SCSAgent detects that the link is down OK OK b The ECS is initiated Failure OK 9 The CSSession is notified which in turn notifies the SCSAgent via MCS An alarm is issued by the SMSEadge OK OK OK OK The database is updated with new commlink and the SCS status is set to red OK OK The SCSAgent sends position updates directly to the CSSession OK OK 3 The GPS receiver is set whilst the ECS node moved beyond The position deviation is discovered by the GPSControlA gent OK OK the boundaries A PositionAlert signal is sent to the MSA gent OK OK SCS node is in An alarm is issued by the SMSEdge OK OK The database is updated with the new position and SCS status is kept red OK OK The failure in point two b is due to the fact that no GPRS modem was inst
188. on during operations of the SCG system such as distributing new parameters through the system but the focus here is sensor data retrieval This system only implements timer based sensor data collection The discussion assumes that all communication links are functioning properly and that all nodes are active The process of retrieving sensor data has taken a two level design As will be shown in the following section each node updates and retrieves its own sensor data with pre determined intervals defined with timers Each node also requests sensor data from a lower level node with a pre defined frequency The interval is shortest for the SCSAgent larger for the CSAgent and the longest interval is the MSAgents When receiving a query for updated sensor data the queried node retrieves latest data from their data agent and sends this to the requesting party The principle with involved actors is shown in Figure 8 28 69 SCG A Distributed Sensor Management Network in ActorFrame mscs MSControlAgent dbe DBEdge 32 oensoripdate 3 1 GetSensorUpdate csca CS csda CS ControlAgent 2 e DataAgent 2 2 SensorUpdate 2 1 GetSensorUpdate 1 3 Hate scsca SCSControlAgent SCSDataAgent ee MSAgent CSAgent Sensors a SCSAgent Figure 8 28 How sensor data is retrieved from the nodes of the SCG system The reason for doing this instead of nodes retrieving sensor data upon request is both to assure more rel
189. or providing GPS data reporting and handling Another project has considered the use of a context manager for handling aquaculture sensor data to a maximum degree the so called FiFaMos project 11 13 SCG A Distributed Sensor Management Network in ActorFrame 4 Sensors The main building blocks of the SCG system are the sensors mounted on the sea cages and control station These sensors provide the data for optimization of production and provide the information necessary for security and maintenance services Handling the different sensors to perform the tasks required is a crucial goal for a SCG system In addition the type of sensors used on an installation must be power optimized reliable and robust enough to withstand the rough conditions experienced in an offshore environment 4 1 Sensor types There are many different types of sensors available all with varying detection methods and sensor interfaces The type of sensors can be optical acoustic thermal chemical mechanical electromagnetic etc The means of sensor data transmission can be continuous or discrete digital or analogue and can require continuous monitoring or can be handled with an interval based polling technique Sensors may have some of the resources necessary to process some data or allow for a certain degree of configuration whilst others simply transmit a raw stream of measurements In general sensors do not parse or log data but simply read t
190. orAgent 1 1 1 RoleConfMsg SensorConfig Data data 1 NewSensor sensorType 1 1 1 1 1 1 1 1 RolePlayMsg 1 1 1 1 1 1 1 1 1 1 NewSensor sensorType 1 NewSensor sensorType 1 UpdateSCSCapabilities sensorType scs 1 l i addSensorToDB sensortype scsname 1 1 1 1 Figure 8 26 The sequence diagram for connecting a new sensor to a SCS The SensorDetectionAgent actor continually searches for new sensors by for instance scanning all available COM ports When it detects a new sensor it identifies its type and sends a RoleRequestMsg signal for a SensorAgent for this type of sensor The SensorAgent for this sensor then handles input and control of the new sensor The SensorManager then informs SCSControlAgent actor about the new sensor and the SCSControlAgent actor informs the SCSSession actor via SCSRouter not shown and the SCSSession actor propagates the information on to its CSSession via CSRouter not shown Information of the new sensor is thus propagated throughout the system automatically If for instance preferred parameter settings for a certain sensor have been altered since deployment of the SCSAgent the SCSSession or CSSession can send new operating parameters back to the SensorAgent actor These parameters can be anything from polling intervals to threshold values A high level communi
191. ore maximum alarms are generated 44 SCG A Distributed Sensor Management Network in ActorFrame There are many elements not listed in the table above as the ECS and FCS links will require attention in the same areas as the MCS and PCS links The requirements can also change depending of the state of the system The issues of privacy and security for this system have not been considered The purpose of this thesis is to create a demonstration of such a system Although non functional requirements are an integrated part of the design they have not been given priority The above discussion serves as an example of issues related to this system 8 2 Overview of the system elements Before designing the actors and elements needed to provide the architecture for the SCG system the elements of the system must be analyzed Determining the environment in which a node is to operate in addition to determining its task enables a design which can effectively handle the scenarios expected from it Note that there may well be more tasks or environmental variables then those identified in the following sections but the system designed in this thesis will be based on the elements presented here The entire SCG system infrastructure is illustrated in Figure 8 5 and the distribution of the agent actors is shown SCG system MS node SCS node CS node MCS antenna PCS antenna 6 E M CSAgent
192. ould be useful 10 1 2 ActorRouter The part of ActorFrame that binds distributed actors together is the ActorRouter As described in section 7 2 2 3 ActorRouter handles the forwarding of messages which are not addressed to any actors in the current actor domain In addition ActorRouter maintains forwarding tables and reports its local actors to a default gateway The method of routing is application level which means that the IP networking is disregarded headers are not read by ActorFrame The ActorRouter s application level routing is simple and does not require much processing power It does not provide any form of route optimization and is in many essences completely cut off from the actual networking technology it uses Due to this the system designer and implementer must know more about the network topology than is traditional In the ideal internet paradigm where all addresses are public with end to end transparency and with the implementation of IPv6 providing the address space necessary for all public addresses and can mask alternating connection points through mobile IP these issues may be of less importance But for the time being the reality is a myriad of connections and connection types with constantly new and re assigned IP addresses When an actor domain is instantiated the IP address this node is to be represented with has to be known This can be difficult in cases of random initiated network connections generated during th
193. ports are also used with caution within a class 5 UML2 0 Collaboration diagrams 53 SCG A Distributed Sensor Management Network in ActorFrame The Edge appendage used on certain actors is to describe and underline that these actors interact with elements beyond the ActorFrame framework These actors provide transparency and levelling between the ActorFrame domain and external services The default ports of the actors have been omitted as have port names on implemented ports The port names generally follow the naming convention FromldToWhold and are presented with each corresponding state machine in Appendix G 8 3 1 SCSAgent The SCSAgent actor is the actor which will represent the SCS node in the system and its structure is shown in Figure 8 11 Its tasks have been defined to the acquisition of sensor data use of certain vital sensor data such as GPS handle sensor data and internal parameter settings and maintain communications with the CS and MS Simultaneously this actor runs the system manipulates the operating system discovers and registers new sensors and handles eventual grid activities This includes not only maintaining both the available services and topology but also allowing access to the SCSAgent from a mobile terminal This fits in to the visions of mobile grid presented earlier SCSAgent lt lt Actor gt gt 0 1 Mobile Terminal Agent Sensor Manager SCS Router Figur
194. ption Language XML eXtensible Markup Language xiii 5 SCG A Distributed Sensor Management Network in ActorFrame xiv SCG A Distributed Sensor Management Network in ActorFrame pisciculture as in every other form of extravagance however it was Lucullus who set the most dazzling standards of notoriety His fishponds were universally acknowledged to be wonders and scandals of the age To keep them supplied with salt water he had tunnels driven through mountains and to regulate the cooling effect of the tides groynes built far out into the sea The talents that had once been devoted to the service of the Republic could not have more spectacularly or provocatively squandered Piscinarii Cicero called Lucullus and Horetensius fish fanciers It was a word coined half in contempt and half in despair excerpt from the Tom Holland book Rubicon The triumph and tragedy of the Roman Republic XV 5 SCG A Distributed Sensor Management Network in ActorFrame xvi SCG A Distributed Sensor Management Network in ActorFrame 1 Introduction In this chapter the background and motivation for this thesis are presented In addition the scope of the project its assumptions and constraints and an outline are given 1 1 Background This project is part of the Sea Cage Gateway project which is an ICT system currently researching the possibilites for remote control manage
195. r handling described in 76 SCG A Distributed Sensor Management Network in ActorFrame section 4 3 The sequence diagram for reactive sensor handling is shown in Figure 8 38 sd Reactive sensor polling sca SensorControlAgent scsca SCSControlAgent scsr SCSRouter SensorValueDeviation SensorDataFormat gt l SensorValueDeviation SensorDataFormat m 2 No action is taken if threshold value is not violated Figure 8 38 The sequence diagram for reactive sensor polling Finally there is the case where the data from the sensor is both to be checked and stored This is similar to the hybrid sensor handling described in section 4 3 The SensorControlAgent actor controls the sensor data against its defined parameters and issues an alert if the threshold is violated If the data is within the boundaries set it is simply stored The sequence diagram for this is shown in Figure 8 39 sd Hybrid sensor polling sca SensorControlAgent sda SensorDataAgent scsca SCSControlAgent scsr SCSRouter SensorData SensorDataFormat alt SensorValueDeviation type 1 1 1 Figure 8 39 The sequence diagram for hybrid sensor polling In the case of a threshold breach on received sensor data the SensorValueDeviation signal is automatically propagated through the SCG system up to the MSAgent Here
196. r to be distributed to new nodes which are connected Parameter settings Centralized parameters regarding threshold values for sensors can be one example Another example is that of update intervals of sensor at the SCS and CS nodes Data storage The accumulated sensor data generated by the SCG system must be stored for analysis and use Data retrieval The data stored must be accessible in many formats all providing support for both different forms of interaction with the data and presentation of it Warning repair activities The node must provide the necessary information for correct warning and repair activities to be initiated Again this is not an exhaustive list of possible MS node tasks simply an example of possible ones and the ones used as basis for the MSAgent actor design 50 SCG A Distributed Sensor Management Network in ActorFrame 8 2 4 Failure modes In this section different failure modes which can occur in the SCG domain and the related actions taken for each of them are presented Elements that can fail are the MCS PCS FCS and ECS in addition to the failure of the nodes themselves This is based on the description given in section 3 1 These will be described more thoroughly later with sequence and collaboration diagrams when they are handled in the system design process The links involved and their adhering system nodes are shown in Figure 8 9 Figur
197. rARC Applied Research Centre Ericsson Norway Haugen JavaFrame 2 5 Modelling Guidelines JF2 5 Ericsson 18 4 2001 Br k Husa G Melby ServiceFrame Whitepaper Ericsson NorARC 22 4 2002 The Eclipse Deveopment Platform Available from URL http www eclipse org NTNU Department of Telematics Ramses User Page URL http www item ntnu no lab pats wiki index php Ramses_ User Page R Haugen Engineering Real Time Systems An Object Oriented Methodology using SDL Hemel Hempstead Prentice Hall 1993 ISBN 0 13 034448 6 Odegaard Location based services using WLAN Project thesis ITEM NTNU Autumn 2006 ADVANTECH ARK 3381 Model Information advantech com tw URL http www advantech com tw products Model Detail asp model 14 1 ITGX8Y amp BU amp PD HaicomGPS HI204III Ultra High Sensitive GPS Receiver URL http www haicom com tw gps204IIll shtml NMEA homepage URL http www nmea org Haicom GPS HI 204III User Manual provided with the GPS receiver upon purchase Teltonika T ModemUSB EDGE6 URL http www teltonika lt en pages view id 2 130 SCG A Distributed Sensor Management Network in ActorFrame 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 telenormobil no Teknisk stette for GPRS oppsett URL http telenormob
198. rFrame xli SCG A Distributed Sensor Management Network in ActorFrame Abbreviations AJAX Asynchronous Javascript and XML API Application Program Interface BCS Backup Communication System CDMA Code Division Multiple Access CS Control Station CSS Cascading Style Sheet DOM Document Object Model ECS Emergency Communication System EDGE Enhanced Data for GSM Evolution FCS Failure Communication System FK Foreign Key GPRS General Packet Radio System HTTP Hypertext Transfer Protocol ICT Information and Communication Technology IM Instant Messaging IP Internet Protocol IPv6 Internet Protocol version 6 JNI Java Native Interface JSP Java Server Pages LAN Local Area Network MAC Media Access Control MCS Main Communication System MS Management Station NAT Network Address Translation OS Operating System PCS Primary Communication System PHP PHP Hypertext Preprocessor PK Primary Key PPP Point to Point Protocol SCG Sea Cage Gateway SCS Sea Cage Station SDL Specification and Description Language SMS Short Message Service SOAP Simple Object Access Protocol SQL Structured Query Language TCP Transmission Control Protocol TDMA Time Division Multiple Access UDP User Datagram Protocol UML Unified Modelling Language UMTS Universal Mobile Telecommunications system WAP Wireless Application Protocol WiMAX Worldwide Interoperability for Microwave Access WLAN Wireless Local Area Network WSDL Web Services Descri
199. rFrame application Operating Operating system system Network Hardware Figure 10 6 The future environemnt for ActorFrame application development The amount of elements to be considered is much larger and more complex than before With the current layering architecture this requires the application to be aware of and handle more and more factors This will require that the application and services development will become increasingly more complicated incurring longer and more complex development How to provide a certain level of transparency from these issues allowing designers to continue to focus on developing and designing services independent of these issues should be an area of future interest and study 123 SCG A Distributed Sensor Management Network in ActorFrame The weakness of only having a single default gateway has also been mentioned previously It could be interesting to examine possible ways of adding redundancy and flexibility to the routing scheme of ActorRouter An option may be the use of anycast addresses or perhaps using redundant servers masked through another Java framework such as JGroup 69 Section 10 3 also mentions the topic of allowing dynamic access from mobile agents to parts of or all of the SCG system data and resources This fits in with a new area currently under research named Mobile Dynamic Virtual Organization MDVO The name refers to the traditional underst
200. rally reduced As a curiosity another motivation for enabling systems for fish farming offshore is available in the United States of America Here each state controls the sea out to five miles offshore Beyond this border restrictions are fewer and the local authorities power is reduced making it a very attractive area for producers 7 This may not be the most ethical reason for pursuing such a system but it is a potential market nonetheless SCG A Distributed Sensor Management Network in ActorFrame 2 5 New demands from markets With increasing focus on origin and quality of food products new demands have appeared for suppliers Not only is price the main focus for the consumer but traceability and ecological production also influence the choice of product This requires efficient logging of all aspects of the aquatic products life cycle from the origin of the fry to conditions experienced during rearing to methods used for cultivation etc By efficiently logging the same factors used to optimize production and providing traceability of fish back to a certain cage it enables a consumer or supplier to see what conditions the product has experienced So the information collected by sensors need not only be beneficiary to the producer but also to the market consumer and in research 2 6 Current related technology used in aquaculture and aquatic environments There currently exist systems for monitoring fish farms
201. rame does not suffice in the distributed ad hoc wireless networks of the future ActorFrame should be able to detect changes in the network connections or at least allow the ActorFrame application to detect these changes and pass these on to the ActorFrame framework An example from the demonstrator of this lacking flexibility of the framework is when the SCS node switches to a GPRS connection thus receiving a new IP address ActorFrame does not appear to provide the possibility of updating the nodes IP address in the ActorRouter One option is to assume one way communication until communication is restored though this will greatly reduce the functionality of the system This also makes the assumption that the IP address received when the main communication link has been restored will be the same as the one registered earlier This is not a situation that can be guaranteed for most systems The CSAgent actor was run on a Linux based operating system The standalone ActorFrame application was slightly unstable on this platform A regularly experienced problem was the instantiation of the actors and theirs action before the ActorRouter was ready Thus the RoleRequestMsg signal to the MSAgent was not sent This often required several restarts before the initiation happened in a more correct order A timer delay on the sending of the RoleRequestMsg could probably have reduced these problems but this problem was not experienced on the MS or SCS node If
202. rame is based on the JavaFrame framework which amongst others provides support for message passing and state machines ActorFrame incorporates role modelling for creating applications based on the concepts of roles actors and plays ActorFrame also provides distribution functionality which enables easy distribution of actors through the use of an ActorRouter instance In addition to providing a framework for modelling services the ActorFrame framework provides possibilities for easy modularity With state machines as a core component distribution is easier and verification is simpler to achieve both manually and with tools supporting such functionality It also provides a certain degree of structural documentation The Ramses tool suite allows for model driven service engineering with ActorFrame and provides automatic code generation from models It also supplies trace functions and input consistency check functions and is continuously being extended and improved 7 2 2 1 Actors roles and plays The building block of a play in ActorFrame is the actor An actor is in essence a state machine capable of receiving and sending actor messages and can contain several inner actors The structure of an actor in ActorFrame shown in UML2 0 notation is shown in Figure 7 3 31 SCG A Distributed Sensor Management Network in ActorFrame actor Actor Figure 7 7 3 The Actor class 42 The basis for ActorFrame
203. re 8 23 A high level communication diagram for a new CS registering with MS The communication 2 1 refers to the distribution of the new update list of CS nodes via the signal CSList among the CSSession actors in MSAgent actor These sessions subsequently distribute the new list to their CS nodes The CSList is distributed to the latest CS in CSSetupParameters signal as previously shown in Figure 8 22 8 4 1 2 Initiating the connection between a new SCS and a CS The procedure for connecting a new SCS node to its CS node shown in Figure 8 24 is very similar to connecting a new CS node to the MS node 65 SCG A Distributed Sensor Management Network in ActorFrame sd A new SCS registers with CS scsr SCSRouter scsm SCSManager css CSSession dbe DBEdge RoleRequestMsg mylD SCSManager i lt lt create gt gt gt scss SCSSession RolePlayMsg RoleConfMsg 1 1 1 1 RegisterSCSInfo mySCSA l 1 1 1 1 1 1 T UpdateSCSList newSCS SCSList UpdatedSCSList E SCSRegistered yourCSS scsList i EL RM SCSSetupParameters _ SCSSetupParameters i l NewSCS newSCSS 1 L t addSCSToDB scsname csname
204. resented and discussed Chapter 7 introduces the modelling framework that is to be used and tools supporting this framework Chapter 8 presents the system design and functionality based on a domain analysis and the inspiration collected from the previous chapters Chapter 9 presents the hardware used for developing and testing the system It describes how specific elements of the system have been implemented and contains a summary of the tests conducted on the system It also presents all the external elements which have been included to realize the design Chapter 10 summarizes the experiences from deployment and discusses design decisions possible extensions and features and suggests areas of future work In chapter 11 a conclusion to this thesis is given Chapter 12 contains the references for this thesis In the following appendixes details of elements in the thesis are presented SCG A Distributed Sensor Management Network in ActorFrame 2 Aquaculture Aquaculture is the marine counterpart to agriculture The principle is controlled breeding and harvesting of marine life Although the concept of aquaculture is not novel the field has undergone several major changes in the past decades From being a fringe industry often used in varying forms in underdeveloped countries aquaculture has become an area of large social and economic focus From feeding the world to maintaining the coastal culture the possibilities
205. ritance concept on the state machines of the system Easy extendibility and reuse through the use of inheritance is one of the advantages state machines offer The ability to use pre defined modules of well proven designed and tested elements and then extend these for specific tasks is a great advantage Ramses does for the time being not support the concept of inheritance For the system implemented in this thesis many actors share the same basic functionality such as the CSManager and SCSManager to mention a few The design and implementation of these could have benefited from inheritance 114 SCG A Distributed Sensor Management Network in ActorFrame Another element discovered during testing of the system was the lacking support in Ramses for arrays As mentioned in the previous section ActorFrame does not provide support for distributing ArrayLists It does however support Arrays Unfortunately Ramses does not support the creation of Arrays The only Array that can be created is the ArrayList This is an unfortunate situation which prevented the distribution of actor addresses in the SCG system a basic element of possible grid computing and node to node independent interaction In addition Ramses does not seem to support the serialization of ActorAddresses as parameters in signals ActorFrame does support the serialization of ActorAddresses but Ramses has not implemented this Such an element should be supported by Rams
206. rk in ActorFrame The GUI generates the PCSRestored signal to the SCS and CS when Reestablish CommLink button is pressed and resets the default GPS position of the GPSControlAgent upon pressing the Reset GPS button 9 2 6 ActorRouter setup When setting up a distributed ActorFrame system the default gateways must be set before initiation How the default gateways are set up is important to ensure that messages are delivered to the correct recipients whilst avoiding unnecessary transmissions over costly links By setting up the default gateways properly it is also possible to a certain degree to create local islands of nodes enabling some private addressing to be used in some situations although this is not ideal At the same time it must be assured that a recipient of signal can be reached independent of where the sending actor is residing It is possible to specify the same default gateway for all actors in the system but as mentioned previously this will incur larger communication costs both economical and resource costs and the hierarchical advantages of the design will be reduced A standard default gateway for all nodes could also be a bottleneck for the system and will not be fault tolerant The default gateway setups of the SCG nodes are shown in Figure 9 14 SCSAgent CSAgent MSAgent scsa ActorRouter csa ActorRouter msa ActorRouter Default Default Gateway Gateway Figure 9 14 The assignment of the default ga
207. rt frequency from the CS nodes must be implemented This will give many possibilities for fine tuning the system as well as defining the correct data for group access and allowing direct interaction to the system WAP SMS IM To provide transparent access to means of interaction with outside actors of the system System alerts regarding drifting sea cages can be given to the rescue teams and administration through an SMS message Groups There are certain essential groups necessary for maintaining the SCG system operable The ones shown in Figure 8 8 are the rescue team and maintenance team These are subsequently a sea cage retrieval team and a node and communication link repair team The right individuals must be notified for the correct incidence This can be achieved through the WAP SMS previously described Users Users interacting with the system either through a dedicated application web server or mobile terminal The MS node environment could also consist of other MS nodes but this has not been considered here In addition to handling the entities in the environment the MS node needs to perform additional tasks These are similar to the ones listed earlier and are displayed in Table 8 7 Table 8 7 The MS node tasks Node tasks Description Parameter control The node must be able to control parameters or variables reported in to it Parameter storage Parameters for nodes must be stored in orde
208. s Compared to allowing all actors control their own timers when sending messages to other actors this method reduces complexity but increases the workload of the Router actor MobileTerminalAgent actor The MobileTerminalAgent is the terminal agent for a mobile terminal wishing to interact with the system This actor could function as a bridge to the CS or MS should the native communication scheme fail This actor has not been implemented since it is beyond the scope of this thesis 8 3 1 1 SensorManager The SensorManager actor in the system represents the sensors connected to a SCS node This provides a layering from the SCS to the sensors and handles the sensors in a dedicated process The SensorManager actor contains two types of inner actors a SensorDetectionEdge actor and SensorAgent actors The structure of the SensorManager actor is shown in Figure 8 13 SensorManager lt lt Actor gt gt SensorAgent Actor 0 Sensor Data Sensor Agent Detection Edge Sensor Control Agent Figure 8 13 The SensorManager actor design As can be seen the SensorManager contains the following five inner actors 56 SCG A Distributed Sensor Management Network in ActorFrame SensorDetectionEdge actor The SensorDetectionEdge handles new sensors connected to the system It listens to the communication ports and reacts when a new sensor is connected by requesting a new SensorAgent for that specific t
209. s Composite State and Profile UML2 0 captures both the static structure of the system and its dynamic behaviour 7 1 1 Inner structure In UML2 0 the definition Part enables the description of the internal structure of a class A part can contain other parts and may create and kill inner parts during its lifetime Parts have multiplicities in the form n m A class with internal structure ports connectors and multiplicities is shown in Figure 4 2 a rd Figure 7 1 A class 2 0 with internal structure ports and connectors 42 Ports define a formal connection between parts and can provide an interface between the class and the environment Ports can either be directly connected to its part or delegate signals to inner parts These are known as behaviour ports and delegation 29 SCG A Distributed Sensor Management Network in ActorFrame ports respectively 42 Unfortunately these do not have separate notations in UML2 0 Connectors specify links between parts to enable communication They can either be connected to a port or directly to a part 42 When a connector is connected directly to a part from a port a form of one way communication arises The part with the port may send a signal to the connected part but the connected part cannot utilize the connector to specify a receiver To respond it must use a specific address or answer to the signals originator Profiles can be u
210. s network form is more complex and requires more processing and bandwidth resources with a corresponding increase of battery power use 18 This type of sensor network is very versatile allowing for both regular logging of sensor data whilst assurance is given that abnormal values are immediately reported when detected For the SCG system this scheme could be applied to several sensors especially those monitoring environment variables which can be met with counter measures An example of this could be a sensor monitoring the algae levels in the sea cage A complete log of the algae levels in the cage could be desirable for research purposes but simultaneously immediate notification of hazardous levels is necessary in order to handle the situation Choosing how to handle the sensors of the SCG system depends on several factors What are the real time requirements of the variable being monitored Is it time critical or non time critical What type of information is being monitored What kind variable is being monitored Is the sensor attaining the values for a log for a control function or both Does battery consumption come second to attaining as much data as possible 4 3 1 Mobile ad hoc sensor networks An extension of the standard sensor network is the mobile ad hoc sensor network They are characterized by a dynamic topology and wireless communication and addresses how this affects sensor handling and routing decisions 19 The ad
211. s CS the SCS should switch to ECS as soon as possible All messages sent between these entities should be replied to ensure reception A timer is set by the router of a SCS to ensure that missing messages are detected Although both the CS and SCS can detect failures only the SCS can switch over to ECS communication But the CS must also be able to detect the failure both as to alert the MS and repair teams but also in the event of a total failure of either the SCS node itself or of the ECS In addition the CS must be able to maintain state integrity when an expected signal fails to make its appearance The interval between the connection checks is defined as the connectionCheckTimer When this timer is triggered the SCSRouter actor sends a SCSConnectionCheck signal to its SCSSession actor This initiates a connectionTimer timer which defines the interval in which a SCSConnectionCheckA CK signal is expected to be received The sequence diagram for link failure detection and handling is shown in Figure 8 41 79 SCG A Distributed Sensor Management Network in ActorFrame sd PCS failure detected by SCS scsca SCSControlAgent scsr SCSRouter osapie OSAPIEdge scss SCSSession css CSSession T connectionCheckTimer 1 1 1 1 1 1 1 SCSConnectionCheck L e lle gt SET NOW time connectionTimer T 1 1 SCSConnectionCheckACK 1 1 1
212. s followed by node To improve readability the node appendage will not always be used 11 SCG A Distributed Sensor Management Network in ActorFrame CS node frame and SCS nodes in addition to providing a land link and sea link for wireless communication After placing the nodes in their designated position the system is initiated Upon initiation the CS automatically registers with the MS and the MS node automatically assigns the resources necessary for administering this node and sends the data the CS node needs to function optimally under current conditions Furthermore when each corresponding SCS node is connected these also automatically register with the CS node and receive correct operating parameters if necessary The CS automatically updates the MS with its new capabilities Sensors which are subsequently connected to each SCS are also automatically detected reported and initiated for use Since the system is largely autonomous the CS needs only to be manned for a few hours every day Otherwise the system controls itself either through self management or through parameters sent from shore When a SCS detects that it is out of its default position an alarm is issued so personnel can be sent to investigate The boundaries for this are shown in Figure 3 3 Figure 3 3 The drifting boundaries for a sea cage The sea cage is represented by the meshed circle in the middle The yellow boundary indicates a
213. s present in each actor project Start the msagent first doing the same as in step 8 Then initiate the csagent and scsagent respectively If several tests are run it can be an advantage to clear out the database before re initiating the system This is done through the SQL command mysql gt DELETE FROM table The tables which need to be cleared are ms cs scs and sensor See Appendix C 135 SCG A Distributed Sensor Management Network in ActorFrame Appendix B System testing In this section the test procedures and tests are shown and commented They are related to the functional requirements stated in Table 8 1 and the sequence and communication diagrams in section 8 4 a Testing the system setup This test was conducted for testing the sequence and communication diagrams depicted in section 8 4 1 which also correspond to functional requirements one and two The results are shown in Table B 1 Table B 1 Test of the system setup functionality Function Expected behaviour Result tested Simulated Distributed 1 CSAgentis a A RoleRequestMsg is sent to the OK OK instantiated CSManager b A CSSession actor is created and OK OK responds to the CSAgent c All CSAgents receive OK Failure notification of the new CS d The new CSAgent receives setup OK Failure parameters and a list of CS e The database is updated with the OK OK new CS 2 SCSAgent is
214. sed to make new concepts for a model In ActorFrame the stereotype lt lt Actor gt gt is used on parts The extensions of this can only be applied on instances of the metaclass Actor 42 7 1 2 State machines UML2 0 offers increased support for modelling state machines and the encapsulation of behaviour in composite states State machines function by accepting triggers in states performing an action and then changing states Sometimes a state change results in the previous state Triggers can be messages timeouts value change or procedure calls 42 7 2 Ericsson s service creation architectures ActorFrame is a Java framework providing a high level of abstraction for creating services It is part of Ericsson s development framework shown in Figure 7 2 and is based on UML2 0 modelling concepts for inner structure and state machines Application MyUserAgent MyTerminalAgent MyCommunityAgent My Roles ServiceFrame Provides Application UserAgents TerminalAgents Community amp gents domain concepts Applicat Lo PeloFrame Provides Role modeling Actors Roles Plays Pattems concepts p Provides UML2 0 CompositeObjects StateMachines Mediators CompositeStates Asynchronous communication Java VM Figure 7 2 Ericsson s development framework 42 The main motivation of these architectures and frameworks is to release the designers from the trivial tasks of handling non service specific techni
215. sibilities putting the system in a suspend modus for battery conservation etc Sensor In keeping with the goal of a self configuring self contained system a Detection separate process for checking for new sensors should be implemented This could also be handled by the OS handling entity but to focus on the task this been kept as a separate process Allowing sensor attachment to be a plug and play process in regards to the system architecture is an important feature These tasks will be incorporated into the system design of the SCSAgent actor 8 2 2 The CS node The CS node resembles the SCS node in many ways and its environment is shown in Figure 8 7 Although the functionality of different processes may vary the basic 47 SCG A Distributed Sensor Management Network in ActorFrame environment and tasks are the same The one major difference is that the CS node must handle all the SCS nodes operating beneath it in the SCG hierarchy Mobile terminal Qe CS Figure 8 7 The CS environment The handling of the SCS nodes and the more direct connection with the MS node are the major extensions compared to the SCS node The elements present in the CS node environment are listed in Table 8 5 Table 8 5 CS node environment descriptions Environment Description element Sensors Each CS node must provide sensor interaction and information retrieval
216. sin StatusName PK somminkid Pk esa StatusID MSId SensorType CommLinkld CSName PK SensorTypeld SCSld SensorName SensorTypeld SensorValue StatusID CommLinkID SCSName Figure 9 9 The SCG database design The arrows indicate a many to one relationship The bold columns indicate a required field not null and PK and FK stand for Primary Key and Foreign Key The database designed has been implemented in a MySQL Server 5 0 Community Edition 60 This is a freely downloadable database available under the GPL License For more information on the MySQL database 61 can be recommended The full specification of the database implementation is presented in Appendix C 98 SCG A Distributed Sensor Management Network in ActorFrame To access and manipulate the database from the Java environment that ActorFrame operates in an interface between them is necessary The MySQL Connector J driver provides this interface As stated in 62 MySQL Connector J is a native Java Driver that converts JDBC calls into network calls into the network protocol used by the MySQL database A SQLInterface class has been written which provides some pre defined methods for interacting with the implemented database This class uses the MySQL Connector J as the SQL driver The SOLInterface class provides several pre defined methods for updating and man
217. sition of the sea cages combined with rough conditions alternative communication links may be necessary This must also be considered in the analysis The analysis should result in the design of a system framework which connects all the elements of the SCG domain together to perform the necessary tasks If possible principles from mobile grid and other comparable technologies shall be considered The ActorFrame framework shall be used to develop a demonstrator showing how a sensor GPS receiver connected to a sea cage may be realized in the framework Assignment given 13 March 2006 Supervisor Rolv ITEM SCG A Distributed Sensor Management Network in ActorFrame Summary This master thesis has been written in connection with the ongoing Sea Cage Gateway SCG project a project investigating the possibility of remotely administering fish farming facilities These facilities consist of sea cages placed offshore and connected to the mainland through wireless communication technologies The sea cages all contain a number of sensors optimizing production and increasing safety Not only must this sensor data be read it must also be transported collected interpreted handled saved and retrieved In addition it is necessary to provide backup communication links in case of failures in the main communication systems The system should be as autonomous as possible allowing it to be unmanned for longer periods of time T
218. stributed Sensor Management Network in ActorFrame Appendix F The LoggingServer class In this appendix the LoggingServer class which creates the connection to the GPS receiver handles the sensor data is presented package no gps import gnu io CommPortIdentifier import gnu io PortInUseException import gnu io SerialPort import gnu io UnsupportedCommOperationException import java io IOException import java io InputStream import java util Enumeration public class LoggingServer private Enumeration portIdents private CommPortIdentifier portInUse private SerialPort serialPort private InputStream inputStream private boolean running true private GPSHandler gpsh public LoggingServer GPSHandler gpsh this gpsh gpsh portIdents CommPortIdentifier getPortIdentifiers while portIdents hasMoreElements CommPortIdentifier port CommPortIdentifier portIdents nextElement if port getName equalsIgnoreCase COM12 portrtnUse Pore try serialPort SerialPort portInUse open LoggingServer 2000 serialPort setSerialPortParams 4800 8 1 0 catch PortInUseException e e printsStackTrace 7 catch UnsupportedCommOperationException e e printStackTrace initiate public void initiate try boolean test true inputStream serialPort getInputStream while test int b inputStream read String String data
219. sults next 55 lt TABLE BORDER 2 gt lt TR gt lt TH gt SCS lt TH gt lt TH gt Status lt TH gt lt TH gt Commlink lt TH gt lt TR gt lt String t scsresults getString SCSNAME String status scsresults getString STATUSNAME String comm scsresults getString commlinkname scesid scsresu ults getint ses if status equalsIgnoreCase gt lt TR bgcolor lime size 5 align center gt lt else if status equalsIgnoreCase yellow gt lt TR bgcolor yellow size 5 align center gt lt else if status equalsIgnoreCase red gt lt TR bgcolor red size 5 align center gt lt S gt lt TD gt lt out sa alte baa gt lt TD gt lt TD gt lt out println status gt lt TD gt lt TD gt lt out println comm gt lt TD gt lt font gt lt TABLE gt lt String lastQuery select sensorname sensorvalue from sensor sensortype where sensor sensortypeid sensortype sensortypeid and scsid sensor scsid sensorresults sensorsql executeQuery lastQuery gt lt TABLE BORDER 2 gt lt TR aliqu center gt lt TH gt Sensor name lt TH gt lt TH gt Sensor value lt TH gt lt TR gt lt while sensorresults next String sname sensorresults getString Sensorname 156 SCG A Distributed Sensor Management Network in ActorFrame 157 SCG A Di
220. t lt lt lt lt lt lt java lang String CSAgent lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt Message rece msqg toStrini se ericsson ef Status Report of type all ACTOR scgs SCGSystem STATE SCGSystem no ntnu item master2006 system scgsystem SCGSystemCS idle se ericsson eto nord _ ACTOR iscgsimsa MSAgent STATE MSAgent no ntnu item master2006 actors msagent msagent MSAgentCS idle se ericsson eto ACTOR iscgsimsa dbe DBEdge STATE DBEdge no ntnu item master2006 actors dbedge dbedge DBEdgeCSiidle se ericsson gt scgsimsa csm CSManager STATE CSManager no ntnu item master2006 actors msagent csmanager CSManagerCS i ACTOR scgsimsa msca amp pMSControlAgent STATE MSControlAgent no ntnu item master2006 actors msagent mscontrolagent MS ACTOR iscgsimsa msr MSRouter STATE MSRouter no ntny item master2006 actors msagent msrouter MSRouterCS idle se er gt ACTOR scgsimsa smse SmSEdge STATE SMSEdge no ntnu item master2006 actors smsedge smsedge SMSEdgeCS idle se gt scgsimsa ae AdminEdge STATE AdminEdge no ntnu item master2006 actors msagent adminedge AdminEdgeCSvidle Status of the report request lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt lt
221. t Actor gt gt Control Figure 8 14 The GPSSensorAgent actor design As can be seen the GPSSensorAgent actor consist only of the inner actors GPSSensorEdge actor and GPSControlAgent actor The SensorDataAgent has not been implemented here due to the lack of need for a log of former GPS positions The GPSControlAgent only compares the latest position to a default position and reacts only upon deviation larger than a certain pre defined threshold Therefore no form of 57 SCG A Distributed Sensor Management Network in ActorFrame data storing agent has been implemented beyond that of the latest position received and the default position The GPSControlAgent actor is directly connected to the SCSControlAgent through ports and connectors providing a direct line of interaction when necessary One example is in the case of an alarm situation 8 3 2 CSAgent The CSAgent actor represents the CS node of the Sea Cage Gateway system Its structure can be seen in Figure 8 15 As earlier described its structure and functionality is quite similar to the SCSAgent The actors represented in this actor are therefore the same as for the SCSAgent actor although their tasks differ slightly In addition the CSAgent actor has a SCSManager actor for administering controlling and interacting with the SCS nodes deployed in the system CSAgent lt lt Actor gt gt 0 1 Mobile _ Terminal Agent Sensor Manager CS Rout
222. t of nodes is dynamic it is difficult to provide such addresses through the provided framework One possible solution is creating an outer actor for the already specified actors aiming to provide such a service The structure of such an actor for the SCSAgent 1s shown in Figure 10 3 117 SCG A Distributed Sensor Management Network in ActorFrame SCSInitiator lt lt Actor gt gt 07 SCSAgent Figure 10 3 The SCSInitiator actor design The SCSInitiator handles the task of assigning a globally unique id to its inner actor SCSAgent This can be done in at least three ways The SCS nitiator actor may upon creation prompt the user for a globally unique address Another option is for the SCSInitiator actor to contact an Address actor for the SCG system which subsequently provides the actor with a unique 14 for the SCSAgent Finally the SCSInitiator actor may itself create a unique id for the inner SCSAgent actor by using for instance the MAC address of the local computer to generate a unique key The id received from any of these methods is then used in a RoleReqMsg signal sent from the SCSInitiator to itself requesting a SCSAgent with this id The same procedure will apply for the CSAgent and MSAgent actors There are many potential additional actors that have been proposed in the system designs in section 8 3 which have not been implemented The inclusion of these actors is a natural extension for an SCG system incorporat
223. ted when a communication link has been severed or a sensor value is incorrect have all been provided through ActorFrame Although giving support for a number of areas the ActorFrame framework is slightly out of its application domain in the SCG system and its original focus of fixed homogeneous network connections is apparent Working with ActorFrame in the SCG domain has provided many possible areas of future work These are not only related to the actual SCG system and ActorFrame but also to other areas representing challenges for further service development frameworks Some key words are mobility heterogeneous networks network and terminal awareness and transparency multiple connection types service discovery and service utilization 125 5 SCG A Distributed Sensor Management Network in ActorFrame 126 SCG A Distributed Sensor Management Network in ActorFrame 12 1 2 3 4 5 6 7 8 9 10 11 12 13 References Diaz Sendra S Sea Cage Gateway Fish Farm Control Station Master Thesis ITEM Telenor R amp D NTNU Spring 2006 Sospedra Cardona R Sea Cage Gateway Management System Master Thesis ITEM Telenor R amp D NTNU Spring 2006 M Beveridge Cage Aquaculture 3 ed 2004 Oxford Blackwell Publishing Ltd ISBN 1 4051 0842 8 Picture of a rigid fish cage Copied 27 04 2006 from URL http www scotland gov uk Resourc
224. tem the actors were distributed on the machines described in section 9 1 1 and the same procedure was repeated The main difference in the setup of the distributed environment was the altering of the ActorAddresses in signals For instance in the simulated version the MSAgent address used is scgs msa MSAgent which translates into scgsystemid msagentid a Actor Type But when the actors are distributed on their respective nodes the SCGSystem actor no longer exists so the MSAgent actors address is msa MSAgent To generate the actors in the simulated system the ActorFrame management console described in section 7 2 2 2 15 used Via this interface RoleRequestMsg signals are sent to the SCGSystem actor and the requested actor is instantiated First a RoleRequestMsg signal for the actor CSAgent and instance 15 sent then a RoleRequestMsg signal requesting the actor SCSAgent and instance The RoleRequestMsg signal for the GPSSensorAgent 15 generated automatically upon a timer trigger in the SensorDetectionEdge actor 9 5 1 Test summary A summary of the test results against the specifed functional requirements is shown in Table 9 3 The full tests for each area are available in Appendix B Table 9 3 Test results against functional requirements R SR Description Test result Simulated Distributed 1 The system must allow for automatic OK OK configuration and r
225. tency was experienced but no more than expected and not enough to present any problems 10 2 Design decisions There are many possible ways of designing a system such as the SCG system But before looking into the design itself a comment is given on the basic domain description presented in 1 2 As used throughout this thesis the SCG domain has had four independent communication systems MCS PCS ECS FCS This was meant to provide a certain level of redundancy in the case of communication failures taking into account the relative instability of today s wireless communication technologies compared to wired solutions 115 SCG A Distributed Sensor Management Network in ActorFrame When implementing such a solution a possible scalability problem arises When the PCS fails SCS nodes are intended to communicate directly with the MS node The load on the MS node can become large in periods of large network instability depending on the amount of sea cages in the SCG system This may not be necessary For the actors residing on the SCS node the CS node is still available independent of the communication link This allows for direct communication with the CS node and only slightly changing the status of the system compared to operations under normal modus This so called BCS Backup Communication System is shown in Figure 10 1 Figure 10 1 Alternative communication links The messages are simply sent over the same link
226. teway of ActorRouter When connecting a CS node to the MS node the address of the RoleRequestMsg signal is the CSManager actor of the MSAgent actor Since the ActorRouter on the CSA gent actor does not have any entries upon initiation the only way for the RoleRequestMsg signal to reach its recipient is if it resides on the default gateway The default gateway of the CSAgent actor is set to the IP address of MSAgent actor The same scenario is applicable for the SCSAgent actor and therefore the SCSAgent actors default gateway is set to the CSAgent actors IP address The MSAgent actor s default gateway is set to its own IP address To minimize the amount of entries in the ActorRouter forwarding tables only actors who must be available for other actors are set visible for the ActorRouter This also reduces the amount of information sent between the ActorRouters and provides a certain level of protection against unwarranted access to actors on distributed nodes 101 SCG A Distributed Sensor Management Network in ActorFrame 9 3 Web Interface To display the changes of the members of the SCG system and display the collected data values and node status a web interface has been implemented This interface continuously reads data from the database and presents it on a web page This interface has been implemented in JSP Java Server Pages but both PHP PHP Hypertext Preprocessor and AJAX Asynchronous Javascript and XML
227. th the closest SCS node It could also provide a wireless connection to installed sensors ActorFrame is currently being extended to support Bluetooth Service Discovery and communication 37 38 6 8 ZigBee ZigBee is a relatively new wireless communication technology with a focus on low power consumption aimed primarily at sensor applications and remote control 39 It is based on the IEEE 802 15 4 standard with a theoretical range of up to 100 metres The bandwidth is set to be between 20 and 250 kb s As for the battery lifetime this can be from several hundred days to over one thousand 40 ZigBee nodes can automatically construct ad hoc networks upon need using an Ad Hoc On demand protocol This technology could be used to allow for wireless connections of sensors to an SCS enabling the entire Sea Cage Gateway System to be wireless 27 SCG A Distributed Sensor Management Network in ActorFrame 6 9 Summary The main characteristics of the communication technologies currently available are shown in Table 6 1 The licensed spectrum column implies whether an existing infrastructure is necessary by vendors with license permissions which can translate into a cost penalty on the amount of data transmitted Elements such as range and data rate are difficult to pinpoint exactly Varying environments and elements can greatly alter these characteristics and field tests are probably necessary to establish correct param
228. the system is actually using LAN connections As the means of communication technology for the ECS GPRS has been chosen for demonstration and testing purposes A GPRS modem shown in Figure 9 5 is connected to the SCS node computer Figure 9 5 The Teltonika GPRS modem The GPRS modem used is a Teltonika T ModemUSB 54 with a USB2 0 connection and external antenna This modem requires an operative SIM card with a subscription that supports GPRS To initiate the modem the T Modem control tool provided with the modem must be used This program searches for the modem authorizes the SIM card controls the PIN and connects to the network The APN Access Point Name of the GPRS connection is also specified here Then the modem can be set up for use with a Windows Dial up Connection 55 This connection needs only to be set up once dial up connection called Telenor GPRS has been created for this system Since the ActorRouter of ActorFrame uses application level routing a public IP address must be obtained from the service provider of the GPRS connection The default connection only provides a private address For the subscription Telenor used for the demonstrator the APN connection must be set to This gives the connected node a public IP address 93 SCG A Distributed Sensor Management Network in ActorFrame 9 2 Implemented elements In the system described in the previous chapter several edge actors w
229. thers could be performed directly on the database residing on the MS node of the inner actors represent a task to be performed or interaction with the environment 59 SCG A Distributed Sensor Management Network in ActorFrame MSAgent lt lt Actor gt gt CSM anager er H AdminEdge 0 m MSCoordinator GroupManager httpEdge SMSEdge MSControlAgentLH_ 0 2 WAPEdge TerminalAgents Figure 8 17 The MSAgent actor design The MSAgent actor initially consists of the following nine inner actors CSManager actor The CSManager actor is similar to the SCSManager actor shown in Figure 8 18 and performs the same task role As the SCSManager actor the CSManager actor has an inner CSSession actor to control and interact with each individual CS node The internal structure of the CSManager is shown in Figure 8 18 60 5 SCG A Distributed Sensor Management Network in ActorFrame CSManager lt lt Actor gt gt CSSession Figure 8 18 The CSManager actor design In addition the CSSession must be able to handle SCS nodes when the PCS fails This can be done by incorporating a ReserveSCSSession actor as an inner actor of CSSession This is shown in Figure 8 19 CSSession lt lt Actor gt gt ReserveSCSSession Figure 8 19 The CSSession actor design When a SCS loses its connection to its CS it requests a ReserveSCSSession actor from its CS node s CSSession actor
230. this thesis is the domain descriptions presented in the master theses Sea Cage Gateway Fish Farm Control Station 1 and Cage Gateway Management System 2 Issues such as reliability and security will not be explicitly explored neither will the utilization of sensor data or context beyond that of the available sensor This thesis does not consider context and utilization of sensor data or how they should be administered However it does consider the need for such issues and relevant suggestions are made The demonstrator is restricted to the equipment available This equipment consists of three computers with varying characteristics one GPRS modem and one GPS receiver 1 4 Project outline In chapter 2 a brief introduction to the field of aquaculture is given and current trends and related technology are presented In chapter 3 the Sea Cage Gateway system is presented in its current status and the domain that this thesis is based on is presented In chapter 4 sensors and sensor networks are presented There are many similarities between sensor networks and webs which can improve and inspire the design of the SCG system Chapter 5 presents grid computing and mobile grids As with sensor networks grid computing can provide inspiration for utilizing all elements available in the SCG domain In chapter 6 the communication technologies currently available for handling the communication links of the system are p
231. tin Preblem e tostring finally seme I muli ST try stmt close catch Exception System out print ln semt nuli ie con con close catch Exception e System out printlnle 0 con null 5H public void updateSCSCommLinkPCS String scsname throws Exception Connection con null 147 SCG A Distributed Sensor Management Network in ActorFrame Statement stmt null int affected 0 try String url Jdbe mysql scgdb Class forName com mysql jdbc Driver newInstance con DriverManager getConnection url user komtek stmt con createStatement affected stmt executeUpdate UPDATE SCS SET commlinkid 2 where scsname scsname 1 System out println The SCS comm status has been updated else System out println The SCS comm status has not been updated catch Exception System out prinEln Problem toString finally Seme Mee try stmt close catch Exception System out printin e tostrang semte nuli con try con close catch Exception e print con null 5 public void updateCSCommLinkFCS String csname throws Exception Co
232. tion to handling the environment the node must perform a minimum of certain tasks to ensure proper flexible and correct operation The minimum set of tasks necessary for the SCS node to perform is given in Table 8 4 Table 8 4 SCS node tasks Node tasks Description Parameter To ensure proper operations certain parameters must be held by the storage SCS node and these must also be adjustable These values could be sensor polling intervals threshold values etc Each individual sensor will also maintain a more detailed configuration set for operations Parameter Elements of the data received both from the sensors and the rest of the control system need to be controlled against the current parameter settings An example of this could be the control of current GPS data against pre determined values based on ideal GPS position A breach of the set parameters indicates a possible failure in the system a situation requiring immediate attention Data storage Sensor data retrieved must be stored for later utilization and distribution but not to the extent of implementing a database Data is ordered as they are still in the possession of their respective sensors OS The system requires that the application running on each node can manipulation interact on the operating system it resides on Elements requiring the use of the operating system can be amongst others battery level status initiating checking network connections and pos
233. to the sequence diagrams displayed and described in section 8 4 3 1 8 4 4 Communications under ECS operation Since the system implemented is supposed to handle a failed PCS link functionality for how the SCG system is supposed to interact has been implemented for this type of situation The sequence diagram describing this interaction is shown in Figure 8 48 86 SCG A Distributed Sensor Management Network in ActorFrame sd SCS reporting in ECS mode scsca SCSControlAgent scsm SCSManager gpsca GPSControlAgent scsr SCSRouter css CSSession SET NOW time sensorUpdateTimer sensorUpdateTimer GetSensorUpdate 2 GetSensorUpdate 2 GPSSensorData position 1 GPSSensorData position 1 1 1 1 SCSGPSSensorData position 1 SCSGPSSensorData position 1 1 1 I SET NOW time sensorUpdateTimer I 1 L 1 Figure 8 48 The sequence diagram for interaction between SCS and MS in ECS mode As shown the sensorUpdateTimer timer is set at a new value This is because the interval defined by this timer implicates how often the sensor data is retrieved and replaces the reporting function previously initiated from the CSAgent This interval also serves to maintain the CSSession address present in the ActorRouter forwarding table previously managed by the ConnectionToMS signal Both these issu
234. ttainment could be of interest for several sensors on the SCG system especially sensors used to analyze environment variables such as temperature conditions 16 SCG A Distributed Sensor Management Network in ActorFrame Reactive In a reactive sensor network sensor nodes continuously periodically sense the environment and transmit only information when threshold values are violated If the sensor data does not incriminate the pre defined threshold values no information is transmitted A drawback is that sensor values are unknown if no threshold value is broken This method saves battery by not transmitting information regularly but leads to an unknown status of environment in which the sensor is operating 18 Such a function could be of interest for the GPS positioning sensor since the position is not of interest unless the sea cage positioning data is indicating that the sea cage is drifting Hybrid A hybrid sensor network incorporates elements from both the reactive and the proactive realms In this form the network polls information regularly but at a lower frequency then common in a proactive sensor network The hybrid network however also transmits data when threshold values are exceeded This adds flexibility to the system and incorporates the best of the other sensor network types Values such as polling intervals threshold values and parameters can all be adjusted to suit the area of application However thi
235. uction costs could be reduced An example of this is the amount of fish feed needed Over feeding results in both a waste of resources and is a source of pollution In addition making sensor data available throughout the life cycle of a fish control and administration can be greatly improved The SCG project incorporates a number of different areas From the system principles and architecture itself to the handling of data to the utilization of the system nodes to the communication technology required and so forth 1 2 Scope The focus area for this thesis is developing an architecture supporting the main principles required for the Sea Cage System This architecture is to be implemented and demonstrated to show the principles in action The design of the system should allow for later extensions and utilization The technology available to provide the services will be briefly presented but the demonstrator presented will be based on the SCG A Distributed Sensor Management Network in ActorFrame available equipment The resulting system will not be a fully functional SCG system but provide a possible basis for the development of one either through the use of concepts presented or as a further development of the system itself The system is to be designed and implemented in the ActorFrame framework utilizing the Ramses tool suite where possible 1 3 Assumptions and constraints The basis for the system development in
236. up in Telenors R amp D Department in Trondheim All node computers were attached to the same local network An illustration of the setup is shown in Figure 9 18 104 SCG A Distributed Sensor Management Network in ActorFrame On location Telenor R amp D Trondheim SCS node 4 GPRS modem Antenna Firewall GPRS gateway Internet Figure 9 18 The demonstrator setup environment A problem discovered during testing was that when the SCS node used its GPRS modem to communicate with the other nodes all signals originating from outside the local network were effectively stopped by the firewall protecting the LAN The ports necessary for ActorFrame 5555 5557 were opened up for the MS node computer and the problem was solved A picture of the nodes with the GPS receiver and the GPRS modem connected to the SCS node is shown in Figure 9 19 105 SCG A Distributed Sensor Management Network in ActorFrame CS node SCS node with GPS receiver and GPRS modem connected MS node Figure 9 19 Picture of the testing elements The agents were then initiated on their subsequent nodes with the Eclipse IDE in the standalone mode of ActorFrame 9 5 Testing During the process of implementing this system tests of the functionality have been conducted continuously Complete testing and analysis of for instance input consistency has not been done However the possibilities of inconsistency have bee
237. within the VHF radio system to provide a data carrying service Telenor Maritime Radio offer two versions of VHF Data a narrowband and a broadband version 32 The capacities are set to 21 kb s and 140 kb s respectively These capacities are for compressed data so actual data transmission is higher for instance it is stated that the 21 kb s link equals a 100 kb s link 33 Current coverage is the southern coast of Norway but full coverage up to Kirkenes is expected by the end of 2006 The system reaches up to 70 km out from the coast VHF Data has always on connectivity and incorporates a standard IP Ethernet interface in the radio for simple connection to existing networks As VHF data rollout has been quite recent only time will tell how the actual implementation works under field conditions However it is absolutely as an interesting candidate for providing ECS and FCS connections 6 6 WiMAX WiMAX is the more common name for the 802 16 standard and is an acronym for Worldwide Interoperability for Microwave Access It is generally considered as a future wireless alternative to cable and DSL The technology provides a range of up to 26 SCG A Distributed Sensor Management Network in ActorFrame 50 km with a theoretical data rate of 70 Mb s but more likely between 500 kb s to 2 Mb s 34 WiMAX delivers great range and great capacity a combination which is unmatched This technology would be a natural choice
238. wn The SCSManager actor via its SCSSession actors then alerts the SCS nodes that they must switch to ECS to uphold communications When in ECS mode each SCS must establish its own connection to the MS to be able to send alert alarms that are vital for secure and safe operation of the fish farm This is the same status as when the PCS between a SCS and CS is down Since in this scenario the PCS between the SCS and CS is still operational the SCS nodes could continue to report to the CS To simplify the situation it is assumed this is not the case A high level communication diagram illustrating the signals sent between the distributed actors is shown in Figure 8 47 85 SCG A Distributed Sensor Management Network in ActorFrame comm FCS failure To all SCSAgents CSAgent ta 22 Pa Database 1 FCSFailed 1 3 ChangeSCSCommLink SCSAgent 1 2 FCSFailed MSAgent I SMS Server 1 4 AlertPCSDown 1 1 InitECS Figure 8 47 A high level communication diagram for a failed FCS The communication diagram essentially displays the same as the corresponding sequence diagram but it also shows how the MSAgent updates the database through the DBEdge actor and issues SMS warning through the SMSEdge actor The sequence diagram reference FCS failure handling in SCS has not been created but will likely be quite similar
239. ype of sensor The SensorDetectionEdge actor could in essence be considered to be part of the OSAPIEdge since it does require interaction with the residing OS In this case it has been considered to be more bound to the SensorManager actor and has been placed here SensorAgent actor The SensorAgent represents the independent sensors to be supported by the SCG system There will be specialized entities of this actor for each sensor type SensorControlAgent actor The SensorControlAgent is responsible for administering and controlling the sensor It can control sensor polling intervals as well as detect sensor value threshold deviations SensorDataAgent actor The SensorDataA gent records data collected from the sensor Upon request report can be generated from the SensorControlAgent on current and historical status This function is most likely to be limited to recent events due to the restrictions imposed on the SCS node Logging may be only to the extent of writing to a text file If the sensor does not require the storage of sensor data the SensorDataAgent is not needed SensorEdge actor The SensorEdge actor handles the direct interaction with the sensor This could require different types of interfaces and is separated from the rest of the system to provide transparency In this system only a GPS sensor is attached to the SCS node The GPSSensorAgent actor implemented is shown in Figure 8 14 GPSSensorAgent lt l

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