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Productization of an HTML5 agent framework

1. Classes and variables for generic and application agent were introduced in the programming guide Examples for creating an agent application and using agent functions were presented Communication component usage was described with an example where agent sends counting results data to another agent New files created for the examples are described in listing 9 3 Listing 9 3 New code files Filename Purpose of file index_count js Example agent application that counts index Getting started with coding agent application with the agent platform index_count html User interface of index_count application count js Fxample agent application that counts compound interest and sends counting results to receiver agent Trying agent to agent communication using communication 9 CONCLUSIONS 58 component count html User interface of count application receiver js Example agent application that receiver counting results from count agent application and shows results in user interface receiver html User interface of receiver application Installation and programming guides were evaluated based on installation and configuration principles and general user manual and technical writing guidelines 59 REFERENCES 1 Braun P Rossak W Mobile Agents Basic Concepts Mobility Models and the Tracy Toolkit 2005 Science Direct E book pp 7 213 2 Mitrovic D
2. Figure 6 2 gmonitor application Gmonitor starts asking load average data from the loadavUrl that you have defined earlier In this example the loadavUrl is http localhost 8892 When you press upload button the state of the agent is serialized and agent is transferred to the agent server Listing 6 5 shows the example of an agent description from the agent log file Listing 6 5 Example agent description LakeusSrc logs agent 10g xxxx auri http localhost 8890 gmonitor js huri http localhost 8890 gmonitor html id 241594 curi variables memory 6 INSTALLATION GUIDE 38 high 0 98583984375 low 0 833984375 count 4 history 0 984375 0 98583984375 0 90673828125 0 833984375 An agent description contains the following information 6 e auri a URL that points to the JavaScript file of the application e huri a URL that points to HTML file the user interface of the application e id unique ID of the agent instance e variables memory local state in terms of names and values of local variables In the user interface a list of active agents is shown List shows the id URL and running status of agents 6 8 Automatizing Node js installation Node js installation script does the steps 1 5 defined in chapter 6 4 It installs node js and uses npm to install mime and socket io modules Script is shown in listing 6 6
3. 3 Transfer the agent Serialized agent is transferred to the receiver agency using a migration protocol 2 MOBILE AGENTS 5 e RI Receive the agent Serialized agent is received using a migration protocol Receiver agency checks whether the agent can be accepted based on the information about the owner and the sender agency e R2 Deserialize the agent Variables and the execution state are restored from the serialized agent e R3 Start agent execution in new thread Receiver agency starts a new thread of control The agent s code is needed to do this Also the code has to be transferred to the receiver agency It can be loaded from the agent s home agency or its code server 1 2 1 3 Mobility models of Aglets and Grasshopper Mobility model 1 defines three views on migration issues e 1 User s view How migration is initiated e 2 Agent s view How data and code are relocated in the network e 3 Network s view How code and data are transferred over the network User s view focuses on phases SI and R3 of agent migration Agent can be immediately started at a remote agency and not at home agency if other agencies support this by providing a communication interface for this purpose Place of code source place from which code can be loaded is in Java CLASSPATH variable or files are in the filesystem and parameter is given during creation Each class file should be stored separately Useful data types for mobile agents are
4. Listing 6 6 nodejs_install script LakeusSrc nodejs_install sh bin sh sudo apt get install y nodejs sudo apt get install y curl sudo npminst sh sudo npm install mime sudo npm install socket io Script can be started from terminal window with nodejs_install sh command 6 9 Automatizing the changing of URLs change_urls sh listing 6 7 is a shell script for changing configuration URLs to configuration js file from command line Script can be started from terminal window with bash change_urls sh command Script automates changing configuration file URLs that was made in chapter 6 3 by changing configuration file directly in editor 6 INSTALLATION GUIDE 39 Listing 6 7 change_urls sh LakeusSrc change_urls sh bin sh Copy configuration js to backup file cp configuration js configuration backup js Get all URLs from configuration file array grep http configuration js grep Eo Get all URL names from configuration file array2 grep this configuration js grep Eo 1 tr d Splitting array to get only url names array2 S array2 0 6 tprintf Ss n S array2 declare i j 0 for i in S array do url Si Saving default URL to new_url variable new url url name S array2 j Printing the name of url printf nSet new Sname n Print new line with default url read i Surl e newline I new line
5. Krishnamurthy 66 introduces three ways on how distributors can make money 1 They provide the product on CD rather than as an online download Most people don t want to download the product from a web site There is money to be made selling the product in CD form 2 There is money to be made in services such as support for installation and answering technical questions The creators of the software can be considered the best suited to provide support 3 Distributors can act as application service providers and help their clients get the latest version of the product as well as updates on the product Licensor of open source software is always free to license his or her software under other terms and conditions Licensee may contact the licensor to determine if the software is also available under a different license 57 4 2 2 The free rider problem All licensees are free to copy and create derivative works without payment of royalties to the licensor If it is important to discourage free riders who create and distribute derivative works then a reciprocal for example GPL license is often more effective 4 OPEN SOURCE 21 than an academic for example BSD license At least with reciprocal licenses everyone is a free rider of everyone else s distributed derivative works because that software is licensed under the same license To be able to avoid free riders adopting one of the non open source licenses should be considered
6. TAMPEREEN TEKNILLINEN YLIOPISTO SAMI TURUNEN PRODUCTIZATION OF AN HTML5 AGENT FRAMEWORK Master of Science Thesis Examiner professor Kari Systa Examiner and topic approved in research council meeting of Computing and Electrical Engineering 5th of May 2014 II ABSTRACT TAMPERE UNIVERSITY OF TECHNOLOGY Master s Degree Programme in Information Technology TURUNEN SAMI Productization of an HTML5 agent framework Master of Science Thesis 58 pages 0 Appendix pages March 2015 Major Software engineering Examiner Professor Kari Systa Keywords Mobile Agents productization installation guide programming guide Mobile agents are autonomous software programs which can move in network and gather information communicate with each other and change information Migration means that mobile agents transfer from one computer system to another Agents have a state that contains variables and functions which are needed to run agent State contains also information about the execution state of the agent Productization is about making software easy to use trough installation instructions configuration scripts and end user documentation The purpose of this work was to prepare the agent platform for publishing This thesis presents installation instructions for the agent platform A configuration script have been made for changing the URLs used by the applications Programming guide helps novice user to develop mobile agent applications w
7. divides software developing companies in technology industry to two groups The first takes the advantage of open source licenses like Apache 55 and BSD 64 which allow them to use these open source components to develop their own proprietary software The second group of companies which stick to GPL 65 and GPL like licenses focus on pure open source software development and utilize the full power of outside in thinking via communities and networks such as universities or other companies Apache License 17 26 version 2 0 grants a copyright and a patent license from contributor to users Redistribution is allowed under following conditions 1 Recipients of the work must be given a copy of the license 2 Modified files include notices about modification 3 All copyright patent trademark and attribution notices must be retained from the licensed work excluding notices that don t belong to any part of derivative work 4 Ifthe work includes notice text file derivative work must include this file Creating and selling customized versions of Apache is allowed License doesn t give permission to use trademarks No warranty is given and contributors are not liable for the damages arising as a result of using the work The MIT License 17 26 gives no restrictions for dealing with the software No warranty is given and authors or copyright holders are not liable MIT license is GPL compatible GNU General Public License GPL 17 18 26
8. is a mobile agent development and runtime platform In Grasshopper two types of agents are distinguished mobile agents and stationary agents The Grasshopper agency consists of the core agency and one or more places Core agency provides a communication registration management security and persistence services A place provides a logical grouping of functionality inside of an agency 2 2 4 Tracy toolkit Tracy 1 is a mobile agent toolkit made in Java programming language Advantages of Java mentioned in the Mobile Agents book 1 are that Java is portable it has security manager and it s pointer model doesn t support illegal type casting Network programming is supported with RMI remote method invocation which helps implementing simple mobile agent toolkits Drawbacks of Java are that it is impossible to obtain execution state of a thread which means that Java based agents can form only weak form of mobility Other drawbacks are the lack of resource control and means to avoid denial of service attacks Tracy has an abstract class Agent and abstract method startAgent It has a migration protocol SATP based on TCP IP Command go initiates migration Agent execution is resumed in receiver agency using Java reflection technique that determines information about classes their variables and methods during runtime All classes whose objects must be serialized must implement interface java io Serializable Class variables are not a part of the se
9. 65 version 2 0 allows to distribute copies of free software receive source code change software or use pieces of software in new programs When distributing the copies all recipients must be given all the rights that the distributor has Recipients must receive or have possibility to get the source code and they must see the license terms No warranty is given Copying and 4 OPEN SOURCE 19 distributing is allowed provided that copies are published with copyright notice and disclaimer of warranty Modifying copy of program is allowed under certain conditions a Modified files must have notices that files have been changed and date when changes have been made b Work that contains any part of the program must be licensed under the terms of this license c Interactive program should print or display an announcement including copyright notice and a notice that there is no warranty and that users may redistribute the program under the conditions and tell users how they can view this license Granting a sublicense to modify and distribute software to third parties not included in the license is forbidden GPL has a Copyleft restriction which means that it doesn t allow users to build proprietary software on top of open source foundations GPL does the most to ensure that software stays open while other licenses are more restrictive LGPL 26 is a lesser restrictive version of the GPL for use with the code libraries that are used in precom
10. It is needed to run agent load and file servers sudo apt get install nodejs 2 Install curl which is needed to get npm installation script from npmjs website sudo apt get install curl 3 Install Node package manager which is needed for installing mime and socket io packages To install npm run script npminst sh from lakeus folder sudo npminst sh Optionally you can run installer from npmjs web page curl https www npmjs org install sh sudo sh 4 Install mime module to nodejs sudo npm install mime 5 Current agent server also needs socket io module for messaging with client sudo npm install socket io 6 5 Starting the servers manually If you want to start servers manually open new terminal window and move to LakeusSrc folder Do following steps 1 Start fileserver node fileserver js 2 Open new terminal window and move to LakeusSrc folder Start loadserver node loadserver js 3 Open new terminal window and move to LakeusSrc folder Start agentserver 6 INSTALLATION GUIDE 35 node agentserverindex js Now you should have three terminal windows open one server running on each 6 6 Starting the servers by using a script file Open new terminal window You can start servers by running the script start servers sh You can check if the servers are running ps ef grep node server js Figure 6 1 shows command line output when servers are started and started servers are
11. and a resource page for uploading data resources GO Publisher Workflow 36 is an enterprise data publication platform that supports multiple data delivery types via the download API Zip archive or WebDAV 72 GO Publisher Workflow is ideal for exchanging large data volumes using open standards Customers can download data using the Download API fetching it directly from the database or GO Publisher workflow can push it to third party Content Management System 4 6 An example CoRED and GitHub CoRED 75 is a web editor where multiple people can edit code at the same time It is available as open source under Apache 2 0 license CoRED is developed at Tampere University of Technology The Source Code of CoRED 76 is available in GitHub It is possible to either clone the Git repository with HTTPS or Subversion or download the source code as a zip package License text can be viewed from the main page and source code files including installation instructions can be viewed from cored folder 4 OPEN SOURCE 25 According to one of the developers Antti Nieminen CoRED was published in GitHub because it is easy to use well known and trusted platform There has been no technical problems in publishing Release hasn t got any attention or gathered outside participants but this was not the target of the release To gather attention and participants it would reguire for example advertising and writing documentation which would help getting sta
12. code is released under AGPL 3 0 41 Launchpad offers users possibility to publish project files for download At first the release must be recorded in Lauchpad In GitHub 19 20 public repositories are used to share Open Source software GitHub offers an option to include a software license when creating a new repository GitHub repositories can be accessed from Git 48 and Subversion 50 clients Google Code 22 offers project hosting with Git 48 Mercurial 49 and Subversion 50 It offers two gigabytes of storage space Code browsing and code review tools issue tracker and project wiki are also included BitBucket 23 offers free source code hosting for Git 48 and Mercurial 49 It offers free unlimited private repositories for up to five developers Features include pull requests and code reviews Codehaus 24 is environment for building open source projects Codehaus accepts only projects that have business friendly licenses Permitted and prohibited licenses are listed in licenses page 67 Projects hosted on the site are selected by reviewers existing Codehaus committers Gitorius 47 provides free code hosting for open source projects that use Git 48 Gitorius is free software licensed under GNU Affero General Public License version 3 41 4 OPEN SOURCE 24 4 5 Data management systems This section introduces publishing systems for open source software These systems are presented here as an option for project co
13. listed The log files of servers can be found from LakeusSrc logs folder Log files are also in html form Go to ogs folder and open file index html with your browser You should see a page with links to log files Press wanted log file name to see the contents You can also see the log files by pointing your browser to application URL logs index htm 6 INSTALLATION GUIDE 36 sami ubuntu LakeusSrc agentframework git start servers sh kill 2589 sh 1 kill No such process sami ubuntu LakeusSrc agentframework gitS ps ef grep node server js 114213235 Pts A 00 00 00 1 2 13 35 pees a 00 00 00 1 2013 35 pcos a 00 00 01 2515 13 35 pts 1 00 00 00 grep color auto sami ubuntu LakeusSrc agentframework git Figure 6 1 Starting servers and checking that servers are running You should have three servers running Jjileserverjs loadserverjs and agentserverindex js If a server is missing from listing you should check error output from a server log file 6 7 Testing the installation with gmonitor To test installation of the agent framework with an example gmonitor application figure 6 2 point your browser to applicationURL gmonitor html In this example it is http localhost 8890 gmonitor html 6 INSTALLATION GUIDE 37 localhost 8890 gmonitor htm 0 58 0 43 0 29 0 14 0 Latest 0 48486328125 High 0 7294921875 Low 0 203125 Count 31 UPLOAD Generateload DEBUG
14. numbers directly from configuration URLs see section 6 10 ConfigurationClass function should be used when referring to the URLs A Configuration object can be created by calling constructor configurationClass which will create object that includes specified URLs 3 3 5 Gmonitor Gmonitor js is an example agent application that monitors load average of a host and tracks the CPU load of a server machine In browser gmonitor shows current load level min and max values and the latest load level history graphically In server history information is still collected Count of taken samples is shown as running status on the agent server list view The specialized parts of gmonitor are 1 Constructor 2 Function continueWork 3 Function preupload 4 Function work Draw function draws the user interface CreateAgentObject function creates agent InitExecution function creates an agent object and starts the agent execution in the browser 3 In this thesis Gmonitor was used to test the agent framework installation see section 6 7 4 OPEN SOURCE 18 4 OPEN SOURCE 4 1 Open Source Licenses Open source licenses 26 ensure that software developers can control the terms under which others can reuse the software they contribute to open source projects All open source licenses share the principle that anyone should be able to use copy and distribute source code and the executable software compiled from it Bilen 63
15. or try instead to make money with a proprietary software distribution model 57 According to Maxwell 62 increasing the number of potential contributors help to avoid the free rider problem because The larger the group of potential contributors the better the odds that someone individuals personal cost benefit calculations will lead them to participate and thus contribute 4 2 3 Motivations for sharing Open Source software Maxwell 62 discusses about reasons why people develop and share open source software One reason is altruism the desire to be helpful to the open source community Some people rely less on financial rewards than on the positive feelings they get from helping others Programmers get the feeling of excitement and accomplishment from writing a program or solving a difficult problem A key reason why programmers are attending to working with shared software is that they are attempting to solve a technical problem of their own If an individual shares code that provides benefits to others that individual may benefit both now and in the future as others share code that they have written Another reason why individuals participate to open source development is increased reputation among their peers This can lead to promotion or give possibilities to getting a better job offers based on the enhanced reputation One reason to participate in open source development is to improve one s programming skills 4 2 4 Out
16. services One solution to avoid attacks is letting agent migrate only to trusted agencies Only agents can complain about agencies agencies have no means to decline a bad reputation 1 Example of malicious host is the host for a shopping agent to find the best airfare for a flight with a particular route To make it s own offer to look the best host could erase information collected by the agent change agent s route or terminate the agent To solve problems with malicious hosts contracts between the operators of agent platforms could be made or trusted third party could supply trusted hardware Agents should be prevented from launching denial of service attack Agent should act only based on information from trusted sources Agents could be held responsible for their actions and agent behavior could be monitored and logged 7 One way to protect mobile agents is that almost all data stored within agent s state or data package must have an expiration date which agencies can verify and reject the agent and the agent s data item if necessary Other way is that when agency has received agent it verifies the state appraisal functions These functions verify specific conditions or invariants in the agents state Agent will have a set of privileges for execution in the agency or this can result as rejecting the agent Privileges can be decided based on the agent behavior at runtime history based decision Firewall is needed to examine agent before
17. the agent e list view of executing agents in server e agent server where agent is uploaded 3 An example gmonitor application also needs URL to server where agent gets load average data Function that returns this URL is called oadavUrl in the configuration file The origin server of the agent is responsible for maintaining and serving all the agent platform files Agent server receives the description of the agent in an HTTP POST reguest 6 In the list view a list of active agents running in the agent server is shown List shows the id URL and running status of agents 6 INSTALLATION GUIDE 32 6 3 Fitting agent platform to own environment Go to folder where you unzipped LakeusSrc package and open configuration js file Modify the return values shown in listing 6 1 You can change different host and port for each URL an example is shown in listing 6 1 and concrete values for this example in listing 6 2 In this example the new hosts are named myhostl myhost2 and myhost3 New ports are port port2 and port3 In test configuration all servers are on the same host so all hosts are named as localhost If your servers are running on different devices you have to make different configuration for each device in this case the port numbers can be the same on each configuration You can modify the return values of the following functions e listUrl Returns URL to list view of executing agents in server Host and port number are th
18. user manuals is recommended to make the sentences simpler and shorter define the responsibility of the action and make the text more interesting This advice has been followed in chapter 6 in sections 6 1 6 7 Using graphics numbered or bulleted lists charts or tables instead of text is recommended where practical Reason to use graphics lists charts or tables is mentioned in 44 These consolidate related information in a logical format and reduce the amount of text a reader must digest In chapter 6 both numbered and bulleted lists have been used when describing the configuration URLs and explaining node js installation steps In chapter 7 functions and variables are presented as bulleted lists Sommerville 45 advices that facts should be presented in a list rather than in a sentence Kennedy 46 advices to get to the point and avoid wordiness and repeating same things many times Installation steps are explained in a very simple short way in the installation guide Installation guide introduces two ways for installing node js and starting the servers That s why user can skip some parts of the installation guide and that s why some things like opening a new terminal window must be repeated many times 9 CONCLUSIONS 56 9 CONCLUSIONS This thesis provided basic information about mobile agent platforms and a short description about the agent platform used in this thesis The term productization was explained and especiall
19. Count agent LakeusSrc index_count js function createAgentObject src html return new Count src html initExecution function is created for initializing agent execution Function creates src and html variables and calls createAgentObject and continueWork functions InitExecution function is showed in listing 7 5 Listing 7 5 Initializing agent execution LakeusSrc index_count js function initExecution var src configuration applicationUrl index count js var html configuration applicationUrl index count html agent createAgentObject src html agent continueWork 7 PROGRAMMING GUIDE 46 Next step is to create index_count html file for the user interface of the application Application is shown in figure 7 1 Index Count Index 12 upload Figure 7 1 Index count index_count html file is shown in listing 7 6 Listing 7 6 index_count html LakeusSrc index count html lt DOCTYPE html gt lt html gt lt head gt lt title gt Index count lt title gt lt meta name viewport content width device width gt lt script src http localhost 8890 configuration js gt lt script gt lt script gt configuration downloadAgent index count js lt script gt lt style gt hl font 30px Times New Roman lt style gt lt head gt lt body onload initExecution gt 7 PROGRAMMING GUIDE 47 l
20. Licensing Licensors decide what license to use for their open source software If possible an existing template license should be used Typical considerations when out licensing software are 57 e The key licensing factor is whether to use a reciprocal GPL MPL CPL 60 OSL 59 or an academic BSD MIT Apache AFL 58 license As a licensor do you want to be able to benefit from improvements made by others Do you want derivative works created by your licensees to be distributed under the same license so that you can incorporate their improvements into your own software e If reciprocal license is selected consider the scope of reciprocity obligation Licenses like GPL contain vague provisions about derivative and collective works Licenses like the MPL have a more narrow definition of derivative 4 OPEN SOURCE 22 works reguiring only files that are changed to be distributed under the MPL The CPL or OSL leave the term derivative works to be defined by the courts under copyright law Scope of any patent licenses that will be granted should be considered Licenses with explicit patent grants are the Mozilla CPL and OSL AFL licenses For these licenses you should decide whether you wish to allow your patents to be used for creating derivative works These licenses have subtly different patent grants Are you prepared to grant a warranty of provenance OSL AFL licenses and similar representations in the MPL and CPL l
21. ML5 agents are composed of two parts 1 Description of the user interface in HTML CSS and image files 2 JavaScript files describing the executable content and dynamic aspects of user interface Generic parts of the agent framework are included into one JavaScript class Agent and concrete agents are implemented by inhering from this class Agent can move between different devices and it is possible to clone agents to create more instances Agents have variable list that contains the state that has been saved and transferred The state of the agent is saved during the migration between server and browser Serialization is done by constructing a JSON string that contains the agent description Transferring of agent is done by HTTP 3 5 6 More detailed information about classes functions and variables can be found in chapter 7 Programming guide 3 HTML5 MOBILE AGENTS 12 3 1 1 Reference models for mobile agents According to 56 a mobile agent must contain an agent model a life cycle model a computational model a security model a communication model and a navigation model Agent model 56 defines the internal structure of the intelligent agent part of a mobile agent This model also defines the autonomy learning and co operative characteristics of the agent Life cycle model 56 defines the different execution states of a mobile agent and the events that cause the movement from one state to another General structure for persi
22. MS Web Map Services WMTS Web Map Tile Service and PNG 4 7 1 IDA Storage Service IDA Storage Service 70 is meant for storing data and metadata The service is intended for the projects of Finnish universities universities of applied sciences and projects of Academy of Finland Universities and institutions have their own IDA contact person who anyone interested in using IDA should contact to A user permit application must be submitted to the contact person Once the institution accepts the application it is signed by the IDA contact person and sent to the IT Center for Sciences CSC 73 4 OPEN SOURCE 26 IDA is based on open source iRODS 74 technology which supports following properties 70 e Data preservation storage procedures virus scans e Data management project group distribution management of copies e Reporting project specific reporting on storage space used e Haka user identification iRODS is released under a BSD license IDA 70 is part of forthcoming long term data preservation service and guarantees at least three petabytes in storage capacity The data owners can decide on openness and usage policies for their own data IDA can be used with different user interfaces browsers online directories and command lines All data stored to IDA must be described in metadata Metadata requirements include defining usage rights for the data URL link to the actual license text must be declared as well as URL links t
23. ON 5 25 sare vaa saavaa vane Tao Say enaa aan p Mea AE E EATEN AESA So 8 Ze SEOUL naam nan man shee cayanrede stoped ds Pond heat pty kee K Makein saneli 10 3 HUMES Mobile A Pertsa oe S tais Ames ven Siena E ketasktat 11 5 AMTOAIEUO SA NNN TANS a 11 3 1 1 Reference models for mobile agents uuuoossn naene 12 3 1 2 HTML5 agents and mobile agent models oooosnnn nnen 13 3 13 PTOIIISOTUT iman sd saamansa oksa onsen iunctevady Okeeess 14 32 PRC STIE SEIN maan Maa an aa TEN TSS aamen a as yom EKES at 15 3 3 Agent to agent COmmMunication uoouossn na a naa naa Kaanaan 16 SA Configuring TTMIESAaSentsssa asassasa os vaa VN katakana 16 Seo MODITO East A ET a Saa asen n ee eae iets 17 4 OPEN OUI A TNT A EN ANTIA EA VIIM AKS As 18 4 1 Oper SOUT CE Licenses onni is kaan a a sat 18 42 Choosing a IiCeisG vts assi otanlbone e a ka an KA tekn somali aak n iisa aan 19 4 2 1 Making money from Open SOource uuuuusss enn aan n naaeen 20 422 Flie free rider problemi sorina iania kanta a a 20 4 2 3 Motivations for sharing Open Source software oussissneen 21 4 24 U PAC CNS II oi unesta avas KTS e SN a a ara HO ES tease se SIS 21 4 3 Things to consider when applying an open source license 22 4 4 Open Source Software Hosting Facilities oossossnn nenne 23 4 5 Data management SY SESTINS seta ance catss cu vesa kaaj aan didenadenn Sasteedeseam
24. ces Orphan agent s owners are no longer interested of it s result or are not available because of a host error Host error can occur when a master agent s agency crashes An energy counter is one solution to avoid unnecessary consuming of resources Every agent has certain amount of energy which it consumes One possibility is that the energy counter can be decreased after every migration Counter could also be decreased for every service access or each message sent Agent must periodically contact to the master agent or home agency for a new energy Otherwise the agent runs out of energy and must terminate Message passing is a type of communication model that allows agents to send messages to each other The sender of the message must know the receiver by name and its current location Point to point is a form of message passing in which a single agent sends messages to exactly one receiver agent In multi point message passing form group of agents must communicate It usually uses point to multi point communication technique in which sender agent wants to send messages to many or all agents of the group Communication can be either synchronous or asynchronous In synchronous communication addresser sender blocks it own execution until addressee has answered with a reply In asynchronous communication addresser sends a message to the addressee and continues its own execution Second communication model is information space Agent writes data to in
25. code publishing places Chapter 5 describes terms related to productization and gives an example of software productization process Chapter 6 contains installation instructions for the agent platform and a description of an installation and a configuration script for the platform Chapter 7 describes the most important functions and variables of generic and application agent This chapter also includes a tutorial for creating a simple agent application Chapter 8 is for evaluation of the installation and programming guides Chapter 9 is for conclusions 2 MOBILE AGENTS 2 2 MOBILE AGENTS 2 1 General information about Mobile Agents This chapter is mostly based on the book Mobile Agents Basic Concepts Mobility Models and the Tracy Toolkit 1 2 1 1 Mobile agents Just like any computer program a software agent performs tasks given by user in a restricted environment The software agent can be a program component or object objects are passive while agents are active Software agents are autonomous they have own plan that is generated in accordance with the user given task No user confirmation is needed every step Software agents communicate with other agents Agents react on environment changes identified events shown by sensors Agents are initiative and plan actively Characteristics of mobile software agents are Agent knows its owner the user who starts the Agent his or her preferences and learns by communicating with its o
26. d receiver agent must be joined to the same communication namespace to be able to communicate 3 Agent to agent communication was demonstrated with an example see section 7 5 where agent sends counting results data to another agent 3 4 Configuring HTML5 agents Configuration of all HTMLS agents is done by modifying configuration js file which includes URLs to The origin server of the agent 3 HTML5 MOBILE AGENTS 17 e list view of executing agents in server e agent server where agent is uploaded e agent server that agent uses to communicate 3 The origin server of the agent maintains and serves all the files All agent applications have the same origin server While the agent moves URL to a resource in the origin server is usually delivered instead of the actual content 3 5 In the list view a list of active agents is shown List shows the id URL and running status of agents http localhost 8891 upload sends URLs to agent code and user interface together with serialized state 5 In the current implementation agent server for communication is the same as the server where agent is uploaded 3 User of the HTML5 agent framework can change the configuration URLs with the help of a configuration script written for this thesis see section 6 9 There were hard coded port number values in the fileserverjs agentserverjs and loadserver js files Modifications to the configuration file have been done to get the port
27. de hosting places presented in section 4 4 DSpace 37 is an open source repository application for academic non profit and commercial organizations building open digital repositories It is free easy to install out of the box and customizable to fit the needs of the organization It preserves easy and open access to all kinds of digital content including text images and datasets DSpace s code is currently licensed under the BSD license DSpace version 4 2 can be downloaded from the files area in SourceForge 38 or via GitHub 39 DSpace documentation is available at Duraspace 40 CKAN 34 is a data management system that makes data accessible by providing tools to streamline publishing sharing finding and using data It is aimed at data publishers wanting to make their data open and available CKAN is licensed under the terms of the Affero GNU GPL v 3 0 41 CKAN offers several ways for adding and editing data Directly via the web interface using CKAN s JSON API 35 or via custom spreadsheet importers Searching includes keyword search faceting by tags and browsing between related datasets CKAN provides metadata title description license for each dataset It offers geospatial features covering data preview search and discovery For communicating and collaborating on data CKAN offers comment and discussion features RSS Atom feeds for changes and revisions and possibility to follow these changes CKAN offers data storage
28. e 1 Proxy Mobile Agents book 1 names this data type proxy because there is a proxy object on each agency that is part of the serialized agent and that is respons ible for transparently forwarding modifications to the home agency e 2 Static Static data is nonmobile and remote access is not possible This data type is common for files or graphical user interfaces whenever they are not of type proxy e 3 Moving Moving data is mobile and the source has been removed Data items of this type no longer exist at sender agency after migration e 4 Copying Copying is mobile and the source is not removed This data type is used for all variables for which the agent has a reference and that are shared with other agents or the agency itself Modifications are not visible at the original data item at the last agency Migration strategies are 2 MOBILE AGENTS 6 e Push all to next The code of the agent and the serialized agent are transmitted simultaneously Connection to the home agency is no longer needed after this one transmission e Pull strategy No code is transmitted with the data transmission There must be open network connection or a fast way to reconnect to the home agency or the last agency the agent came from e Push all to all The complete code of an agent is sent to all destination platforms agent is going to visit Network s view means all aspects related to data transmission Agent toolkits are using different transmissio
29. e same as in uploadUrl list HTTP GET gets a list of active agents as an HTML file that can be shown in browser 5 e uploadUrl Returns URL to server where agent will be uploaded The server can be running on different device than the origin server of the agent In this case host part must be modified upload HTTP POST sends URLs to agent code and user interface together with serialized state 5 e applicationUrl Returns URL to origin server of the agent Knows the location of the JavaScript and HTML files needed to run the agent application e loadavUri Returns URL to server where agent starts asking load average data If the server is on different device host must be modified This URL is not part of the agent platform and is modified because an example gmonitor application uses it 3 More information about these URLs can be found from section 3 3 Script for changing these URLs from the command line is described in section 6 9 Modifications that help to change the ports of agent file and load servers have been described in section 6 10 Listing 6 1 Highlighting the modifiable parts of URL LakeusSrc configuration js this listUrl function return http myhost2 port2 list this uploadUrl function return http myhost2 port2 upload this loadavUrl function 6 INSTALLATION GUIDE 33 return http myhost3 port3 this applicationUrl function return http myho
30. eded a ad ee aerate E hE 59 1 INTRODUCTION 1 1 INTRODUCTION The purpose of this work was to study productization and prepare a mobile agent platform for publishing by writing installation and programming guides for the platform Open Source licenses were studied Software hosting facilities were searched and data management systems for source code publishing were studied The initial version of the agent platform described in this thesis was made by professor Kari Syst at Tampere University of Technology on spring 2012 Version used in this thesis is a second iteration of agent platform that was made by Laura Jarvenpaa on spring 2013 Problems for this thesis were What is productization and especially installation and configuration during productization How to write a good installation guide How to make installation of the agent platform easier How to write a good programming guide How to make programming agent applications with the agent platform easier What kind of open source licenses are there and what are their biggest differences Where to publish mobile agent platform source code Chapter 2 contains general information about mobile agents and examples of mobile agent platforms Mobility models communication and security of mobile agents are briefly described Chapter 3 gives an overview of mobile agent platform used in this thesis Chapter 4 contains information about open source licenses software hosting facilities and source
31. enen 24 4 6 An example CoRED and GitHub tecsesaceseissaatiesavoysctecentoareapsisdneaston enens 24 4 7 AVAA open access publishing platform cceeceeseeeceeeteceeeeeeteeeteeeees 25 4 11 IDA Storage ServiCensmmaakettsavs skn raa a at e spyke sea 25 4 7 2 Comparing AVAA and IDA with data management systems 26 4 8 Proposal for license and publishing platform cece neen 26 8 9 PRO GUC TAAL Nay tase maasian Saatanan snka ae Taa E seats astaan 27 51 Titto0UotiOtimutusasussaana sve astatoinan Tuva cote e detects dun ea a LK Kea SAAS 27 Seer ListaavhsysmeK a e am a a E nae ew ates ea 27 5 3 Config ration sron an r E kanaa E E A E Taa VAN Task 28 5 4 Software productization process A en Aa 29 Enst llotion CAS n maat compute iatrou soe nowy op vbnsed maas ava heidloe weewnasuaneenavsuateans 31 Od Cmpackinotilesmmuomsiassamsviovuase astu aate ms Oui asua Ts G i 31 6 2 Preparations for testing the installation sossssss ennnen 31 6 3 Fitting agent platform to own environment esssesseseessessresreesresressreseees 32 OA Node js Installattoiu sssmmsssuaatuavsst amis reri i AR EERE nn 34 6 5 Starting the serversmantally ssc dass wi ctacecaiisatulneauaeunciGsaueiets 34 6 6 Starting the servers by using a script file eee ee cceeececeesteeeeeeteeeeetneees 35 6 7 Testing the installation with gmonitor uosssssn n aa en aaeeen 36 6 8 Automatizing Node js
32. entation WWW Referred 13 10 2014 Available http www literateprogramming com documentation pdf 46 Kennedy Patrick M Technical Writing Tips Tech Directions November 2004 pp 22 23 47 Gitorius WWW Referred 23 10 2014 Available https gitorious org 48 Git A free and open source distributed version control system WWW Referred 23 10 2014 Available http git scm com 49 Mercurial source control tool WWW Referred 23 10 2014 Available http mercurial selenic com 50 Subversion WWW Referred 23 10 2014 Available http subversion apache org 51 Bazaar version control system WWW Referred 23 10 2014 Available http bazaar canonical com en 52 Apache Allura Forge software for hosting software projects WWW Referred 23 10 2014 Available https allura apache org 53 Fogel K Producing Open Source Software How to Run a Successful Free Software Project WWW Referred 23 10 2014 Available http producingoss com en index html 54 GNU GPL version 3 WWW Referred 23 10 2014 Available http opensource org licenses GPL 3 0 55 Apache License Version 2 0 WWW Referred 23 10 2014 Available http opensource org licenses Apache 2 0 63 56 Green S Somers F Software Agents A Review WWW Referred 5 11 2014 Available https www scss tcd ie publications tech reports reports 97 TCD CS 1997 06 pdf pp 26 39 57 Rose
33. entations Navigation communication and security models are on the initial stage Agent model 3 includes the management of the inner state of the agent Life cycle model 3 main life cycle of the agent follows the persistent process life cycle described in section 3 1 1 During its life cycle agent may visit several browsers and agent servers 5 An example life cycle is described in figure 3 2 Origin server Agent server 1 Agent server 2 2 Push to 1 Start and server initialize agent Browser 1 Browser 2 Figure 3 2 HTML5 agent life cycle 5 In step 1 figure 3 2 agent is started in Browser 1 when it is downloaded from its origin server Agent is initialized and the execution begins In step 2 agent is pushed to agent server where it can continue its execution The agent server gets the internal execution state of the agent and URL to the application code In steps 3 5 agent moves from one environment to another preserving its internal state and continuing execution In step 6 the execution is terminated 6 3 HTML5 MOBILE AGENTS 14 The origin server and agent server are HTTP servers that can be accessed with HTTP requests Agent is fetched for execution with GET and pushed to server with POST Because agent can run with or without user interface the execution part of the HTML5 agent needs to be separate from the user interface 5 Computational model 3 of application needs to be run i
34. ently customized developed and produced Focus starts to change from customer orientation to market orientation Customer specific parts can be created if necessary In stage 6a there is a need for customizable part on product Compared to stage 5 releases are the same for each customer Stage 6b is defined as standard software product No customized features are included in product and product is completely configurable 12 6 INSTALLATION GUIDE 31 6 INSTALLATION GUIDE This installation guide is made for Ubuntu 12 04 LTS Guide is valid for platforms with 64 bit operating system 2 Gigabytes of memory and AMD Turion 64 X2 Mobile Technology processor Installation guide was made with a laptop computer 6 1 Unpacking files Download LakeusSrc tar gz package and unzip it to new folder In this example LakeusSrc package is downloaded to the home folder home username Open terminal window and check with s that you have LakeusSrc tar gz package in your home folder Extract tar gz package tar zxvf LakeusSrc tar gz After this command you should have a folder named LakeusSrc in your home folder including all agent platform files 6 2 Preparations for testing the installation To test the installation of the agent framework with an example gmonitor application on a local server the agent must be configured Configuring the agent is done by modifying configuration js file which includes URLs to The origin server of
35. er html files 7 PROGRAMMING GUIDE 48 Compound interest count Years 4 Intermediate results 12 000 14 400 17 280 Result 20 736 upload Figure 7 2 Compound interest count user interface New values are added to Count agent constructor see listing 7 7 e Starting value for count e multiplier result e results array for storing several intermediate results is created index for count number of years Listing 7 7 New values in Count agent constructor LakeussSrc count js that startValue 10 that multiplier 1 2 that result 0 0 that results new Array that index 0 that registerVar startValue that registerVar multiplier that registerVar result that registerVar results that registerVar index 7 PROGRAMMING GUIDE 49 Counting is done by calling multiply function from work function In multiply function listing 7 8 provisional result is multiplied with multiplier and result is stored to result variable and results array Index is increased by one Listing 7 8 Multiply function LakeusSrc count js Does the counting and stores results that multiply function console log in multiply value that result if value 0 value that startValue result parseFloat value parseFloat that multiplier result is the next value to be multiplied that result result toFixed 3 that results push result toFi
36. es mentioned in 3 would be even better than the command line based configuration In 42 a list of techniques is presented that might help writers to engage their audience One advice for the writer is to Be sure the sense of a paragraph does not rely on its title This advice is important because some of the readers might skip over subtitles headings and introductions In this thesis the first paragraphs of the 8 EVALUATION 55 installation and programming guides explain the mission of the chapter so chapters are not relying on their title Ganier 43 gives design principles for improving procedural instructions One of them is to use clear precise and prominent headings to facilitate comprehension and execution of the instructions In installation and programming guides headings are mostly named by the task or subject class filename which is explained in the chapter Execution of the action is easier if the presentation order corresponds to the execution order 43 The installation guide follows this advice by processing things in same order they should be executed The execution steps should be numbered and presented in a vertical sequence to improve readability of the instructions and to allow users to find specific information more quickly 43 In the installation guide node js installation instructions as well as instructions for starting the servers follow this advice In 44 using a conversation style and active verbs in
37. et al Radigost Interoperable web based multi agent platform J Syst Software 2014 http dx doi org 10 1016 j jss 2013 12 029 3 Jarvenpaa L Development and evaluation of HTMLS agent framework Master of Science Thesis 4 GitHub Istalling Node js via package manager WWW Referred 28 5 2014 Available https github com joyent node wiki Installing Node js via package manager 5 Jarvenpaa L et al Mobile Agents for the Internet of Things IEEE 2013 6 Syst K Mikkonen T J rvenp L HTML5 Agents Mobile Agents for the Web Springer Verlag Berlin Heidelberg 2011 7 Borselius N Mobile Agent Security Electronics amp Communication Engineering Journal October 2002 8 Aglets WWW Referred 24 6 2014 Available http aglets sourceforge net 9 Wong D et al Java Based Mobile Agents Communications of the ACM March 1999 Vol 42 No 3 10 D mel P Mobile Telescript Agents and the Web Compcon 96 Technologies for the Information Superhighway Digest of Papers 1996 pp 52 57 11 Hietala J Kontio J Jokinen J Pyysiainen J Challenges of Software Product Companies Results of a National Survey in Finland 10th International Software Metrics Symposium 2004 pp 232 243 60 12 Artz P Van De Weerd I Brinkkemper S Fieggen J Productization Transforming from Developing Customer Specific Software to Product Software Lecture Notes in Business Information Pr
38. formation space and other agents can read it The most important difference to message passing is that an agent doesn t have to decide which piece of information must be sent to whom Full information approach assumes that every agency knows the current location of all agents in the system This approach is good for delivering messages In no information approach no agency has a direct knowledge of the current location of agents Locating agent for message delivery is difficult Whether to favor full information approach or no information approach depends of agent Is the agent mobile and does the agent receive a lot of messages 1 2 MOBILE AGENTS 10 2 4 Security Agent can consume resources of the hosting environment This can lead to situation where agency can no longer provide it s usual service to the other agents Agent might try to gain unauthorized access to the agency This can be solved using Java sandbox technique Agent can attack other agents In Java this might be avoided by defining separate class loader to agent Malicious agency is an agency that tries to attack mobile agents Mobile agent must authenticate on every agency and agency must authenticate to the agent Agency can attack to other agencies communication link It can tamper or delete data of other agencies Agency can attack to agent to cause another agency to malfunction In case of black box attack agent is executed several times changing input parameters and calls to
39. g code entirely seeking permission to include third party code or replacing it with 4 OPEN SOURCE 23 open source code providing equivalent or similar functionality The presence of third party technology can also affect on selecting an open source license To ensure that the source code is ready for public distribution remove or revise inappropriate language and comments intended for internal viewing only Bugs should be searched from the source code and fixed before releasing the source code Woods amp Guliani 26 address that code should be organized in a way that invites understanding and that reveals at least some organization Code should be modularized and grouping of the modules together should have considered A naming convention should have been rigorously adhered to If the code files include code that is already licensed under certain license like XMLAHttpRequest js that is licensed under MIT license it is important to check that those licenses are compatible with the chosen license 4 4 Open Source Software Hosting Facilities SourceForge 15 is a website for finding creating and publishing Open Source software for free It offers custom project page and download status information SourceForge platform is Allura 52 which is released under the Apache license Launchpad 16 21 uses Bazaar version control system 51 for code hosting Launchpad includes bug tracking code review and translation tools Launchpad source
40. gent class Generic agent 3 is the base class for each agent application Generic agent should not be instantiated because its purpose is to provide the generic parts of the agent to all agent applications Inheritance between the generic agent and the application agent is done by using functional inheritance pattern described in 32 7 1 1 Functions Generic agent is responsible for preserving the agent state Saving inner state of agent is done using register Var variable name function It registers variables to the state of the agent Another function for the state management is e setMemory variable list Resets the memory of the agent to the given variable list Clears all the previously saved memory variables and their data Functions for serialization and transfer management e serialize Returns agent description This method is for the framework and not usually called from the application code e preupload Used when agent needs to do something before the upload Generic agent has no implementation for preupload e upload Calls serialize function and transfers the agent description to the server Functions for the execution management of the agent are e continueWork Initializes the arriving agent and returns the agent variables and memory in restart of the agent e setRunInterval interval value Sets the interval in milliseconds for the calls of work function e work Defines what agent is supposed t
41. glets IKV Grasshopper and Tracy Reasons to use mobile agents are 1 e Task delegation which helps to avoid the information overload because user can focus on other things while agents perform tasks for user e Asynchronous processing Mobile agents are not dependent on network connections Network connection is only needed for the first migration This ensures that agents can be started from mobile devices that offer only limited bandwidth e Adaptable service interfaces Mobile agents offer a chance to design a client driven interface that is optimized for the client but also adaptable to different server interfaces e Code shipping versus data shipping Instead of transferring data to the client data shipping it can be transferred to the location of the data code shipping by means of mobile agents Only the relevant data is sent back to the client This reduces network traffic and saves time Benefits of mobile agents listed in 5 are e Mobile agent can reduce network load by preprocessing sensor data e Agents overcome network latency e Agents encapsulate protocols agents are good tools for introducing new protocols or data formats e Agents execute asynchronously and autonomously There is no need to generate network traffic for every execution Domains where agents are noticed useful are electronic commerce and information retrieval One advance of agents is that they can filter sensor data 1 2 1 2 Migration Mig
42. h application specific user interface 3 3 2 Agent server Core components of the agent server are a HTTP server and a virtual machine executing JavaScript 5 Agent server consist of server router and handlers In agent server dependency injection design pattern 31 3 is used The agent server receives the description of the agent in an HTTP POST request 6 Then the following steps 6 are executed 1 The executable JavaScript file is downloaded from the origin server of the agent 2 The required run time structures are created 3 The function continueWork of the downloaded agent is called 4 A timer to periodically fire work function is initialized When the agent is running in server it runs in headless mode and the HTML and CSS files are not needed In headless mode the central components are the JavaScript files 5 3 HTML5 MOBILE AGENTS 16 3 3 Agent to agent communication Real time agent to agent communication 3 is made with node js 29 module socket io 30 In browser to browser messaging server is always needed Agents must use communication component to get connection to the agent server Agent sends information in JSON form to agent server and agent server passes the information to other agent Agent to agent communication using agent server is described in figure 3 4 Communication Communication component component Agent server Figure 3 4 Agent to agent communication 3 Sender agent an
43. icenses or do you prefer to disclaim all warranties In some countries you may have to accept warranties regardless of what your license says Do you want a defense against patent infringement lawsuits and should the defensive strategy terminate only patent licenses Mozilla and CPL licenses or both copyright and patent licenses OSL AFL licenses for patent infringement claims Is it sufficient to mandate an express condition that the software cannot be distributed if there is a patent infringement claim against the software i e the GPL license Do you want your license to be interpreted under copyright law only i e the GPL or under both copyright and contract law i e almost all other open source licenses Rosen 57 advices consulting one s attorney before actually crafting or selecting a license 4 3 Things to consider when applying an open source license Hecker 61 addresses things that company has to do to implement an open source strategy If your open source product shares a common source code base with others of your products that will remain proprietary make sure that open source development can proceed without complicating your other internal development efforts This may require licensing considerations and appropriate modularization If your product includes technology licensed from the third parties you must treat third party code specially to create a releasable product Ways are removin
44. idelines e Avoid asking unnecessary questions Postinstallation confirmation 27 e Verify that the right files were copied to right locations or execute the installed software and invoke any number of manual and or automated tests Check if the system is giving the right results Log the results of postinstallation confirmation e Test installation and uninstallation e Provide automation scripts for your setup 5 3 Configuration Configuration 26 is the process of controlling the software s behavior Mechanisms controlling software behavior vary from settings in property files and databases to small scripts that are executed at predefined points Mechanisms can be undocumented or documentation can be in the form of comments included in property files The best programs have interactive environments for changing settings For open source software mechanisms are found more trough trial and error or reading code rather than trough some comprehensive documentation Beginners need information about what settings are needed to make databases web servers and network ports to behave properly For beginner and intermediate level users the most useful documentation comprises a step by step tutorial of how to get a project running Configuration principles according to 27 e Something should be a configuration parameter only if the system can t function without it being set such as a proxy server Otherwise make it a customization para
45. includes writing installation scripts creating graphical configuration tools and creating engineering and end user documentation Installation is the process of fitting software into the environment in which it will run For an open source product installation might mean unzipping the source code compiling the program and then figuring out how to fit it into your production or development environment 26 According to 27 installation precondition verification includes e Making sure that you have enough free space for the target application e If your software requires any connections to other entities check them before you begin the actual installation 5 PRODUCTIZATION 28 Things to consider during the installation process 27 e Tell the user how much time the installation process will take e Provide the user information about installation progress This can be provided with the progress meter or via command line or user interface e Record the operations performed and the actions taken during installation to the log files Capture user responses to questions raised by the installation e Make the installation process interruptible with the expect that it will be interrupted at least once e Or make the installation process self aware so that it can restart itself if needed e Other option is to provide an installation checklist that breaks up installation process into series of smaller steps e Follow platform specific gu
46. ing CKAN offers good features for publishing finding storing and managing data 5 PRODUCTIZATION 27 5 PRODUCTIZATION 5 1 Introduction According to 26 productization means making software work for the general case and making it as easy as possible to use According to 25 productization is a process where software is converted for re use into a product The target of productization is configurable application built upon a programming framework Productized code is typically easy to install configure and use Code is made using coding file format and interface standards According to 11 productization includes technological elements from designing a product to commercial elements of selling and distributing a product Products vary from standard packaged software products to customer tailored software Examples of packaged software products are word processing packages spreadsheets business software and operating systems Productization tends to came late to open source products In many projects attitude towards productization is dismissive This weakens project s appeal to beginner and intermediate skill levels in IT departments and other groups Productization can help making software available to a larger community It can reduce the learning curve for project participants Lack of productization causes the company support costs or customer frustration 26 5 2 Installation Work that takes place during productization
47. installation sousosss n nannaa eeeseet 38 6 9 Automatizing the changing of URLS cuuesuussu enaa naan naene 38 6 10 Removing hard coded server port number values osssssisnn ennnen 40 6 10 1 ParsePOtt unetion summaan salaa tcipeadeleiant ncsandone vias abel aenbats Ramsin 40 6 10 2 SETE OMON OS i ANSI INH SANAN Ea 41 PHO STAM IS G ldemir o aT kase ti usn segue sta dai sakata OKS 42 Tal gt Generic agent classar saava ma omaat lade lastacpaneaguee Sa vas 42 TAL RUNG CONS omamassa mao vasa ika oheen Hasa a sadan kassa ansa N E masa 42 GN MARA Daa Sosis ae Kan lkv ona Os Rage a ae ass 43 TZ Application aDetitins se sau sncrelagtenbansa syon a han cise tes osaan enA an Isp naa naakka taita Na 43 72 1 Compulsory functions for application agent uuuosssnn neen 43 7 2 2 Additional compulsory functions for application agent 43 7 3 Creating an example agent application ouosssn n a neen 44 74 Adding new values and functions to Count agent uuosssn nenne 47 7 5 Getting the communication WOorking uuossnn na naene eneeen 50 7 5 1 Sending information from agent to another agent oossn 50 7 5 2 Receiving information from Count agent uuusussn nnen 52 Evaluation e aeoea e ALAN SO Akasa E SULAN SIA LAI KES ENT AROA smn asa 54 CORCIUSIONS 22 4 soks OS en out a anche oe ua manasi 56 References sch ieteent t sm de
48. ion component communicates with the agent server Communication component should be required at the beginning of agentserver_handlers js file The beginning of the file should include the line var CommComponent reguire communication js CommComponent Without reguiring the communication component uploading agent won t work 7 5 1 Sending information from agent to another agent Information sending from agent to another agent is made using the communication component At first communication component is required from communication js file at the beginning of count js file Then a new CommComponent variable is initialized in Count agent constructor listing 7 10 Callback function is given as a parameter so that communication component can provide the received information to Count agent Namespace where communication component will be connected is set as count by calling the setNameSpace function After that connection to the agent server is initialized and communication namespace is created by calling the init O function Listing 7 10 Creating and initializing communication component LakeusSrc count js 7 PROGRAMMING GUIDE 51 that commComponent new CommComponent function message alert message that commComponent setNameSpace count that commComponent initIO Counting parameters and results are send to receiver agent by calling sendMessage function of communicatio
49. ions to the configuration file have been done to get the port numbers directly from configuration URLs New parsePort function listing 6 8 is added to configuration file for parsing agent file and load server ports from URLs Listing 6 8 Function for parsing port from URL LakeusSrc configuration js this parsePort function url var arrl url split var arr2 arrl 2 split return arr2 1 parsePort function splits URL into parts using marks as a delimiter Split parts are stored to arr array The part of the URL including host and port divided by mark is then split and stored to arr2 array and second item of array is returned 6 INSTALLATION GUIDE 41 6 10 2 serverPort functions Agent file and load servers are calling different function to get the port value These functions are agentserverPort fileserverPort and loadserverPort listing 6 9 Listing 6 9 Functions returning server ports LakeusSrc configuration js this agentserverPort function return this parsePort this uploadUrl this fileserverPort function return this parsePort this applicationUrl this loadserverPort function return this parsePort this loadavUrl These functions call parsePort function for getting the port from right URL and return the result of parsePort function to servers 7 PROGRAMMING GUIDE 42 7 PROGRAMMING GUIDE 7 1 Generic a
50. is not empty new line is saved to new_url variable if n Snewline then new url newline fi Replace URL with new URL in configuration js file sed e name N s url new_url g configuration js gt configuration js tmp amp amp mv configuration js tmp configuration js 6 INSTALLATION GUIDE 40 J Jj 1 done Configuration file is stored to backup file configuration_backup js so that user can restore it if something goes wrong when setting new URLs Script finds URLs and URL names from configuration js file using grep Script stores URLs and URL names to arrays Script goes url array trough in for loop and asks user to set new URL New URL is changed to configuration file using sed If user enters empty line the old URL is stored to configuration file Sed uses tmp file to restore changes if changing URL causes an error 6 10 Removing hard coded server port number values 6 10 1 parsePort function As mentioned earlier in section 3 3 there were hard coded port number values in the fileserverjs agentserverjs and loadserverjs files Problem arises in a situation where user changes port number of certain configuration URL to configuration file but doesn t change port number to server file If user changes applicationURL port the port number should be changed to fileserverjs file as well Otherwise application wouldn t start in browser To solve this kind of problem modificat
51. it leaves agency because it could carry a piece of code with it Only agent replication can detect an attack and recover the error 1 3 HTML5 MOBILE AGENTS 11 3 HTML5 MOBILE AGENTS Research papers 5 6 56 and thesis work 3 as main references 3 1 Introduction The goal of HTML5 as mentioned in 6 is to allow the development of complete client side applications HTML5 allows more applications to be run in browser Browser is increasingly acting as an application platform and applications can store their internal state in the server for future use In HTML5 agent framework the executable code can be moved with the internal state of the application Agents can continue their execution while being stored in the server and the running applications can be later retrieved back to the browser The agents are implemented as HTML5 applications and are therefore called as HTML5 agents 6 Mobile agent framework used in this thesis consists of HTML agent base class and agent server Agent base class works with user interface inside browser or in headless mode in an application server 3 Code on demand paradigm 33 is used for getting the static files of the application when agent travels in network Agent server represents mobile agent environment in server side and browser represents mobile agent environment in client side Implementation of server side execution environment is done with node js 29 Like most HTMLS applications HT
52. ith the agent platform To make publishing easier open source licenses software hosting facilities and data management systems have been studied Il TIIVISTELM TAMPEREEN TEKNILLINEN YLIOPISTO Tietotekniikan koulutusohjelma TURUNEN SAMI HTML5 agenttisovelluskehyksen tuotteistaminen Diplomity 58 sivua O liitesivua Maaliskuu 2015 P aine Ohjelmistotuotanto Tarkastaja Professori Kari Syst Avainsanat Liikkuvat agentit tuotteistaminen asennusohje ohjelmointiohje Liikkuvat agentit mobile agents ovat autonomisia ohjelmia jotka liikkuvat tietoverkossa ja ker v t tietoa kommunikoivat toisten agenttien kanssa ja vaihtavat tietoa Termi siirtyminen migration tarkoittaa mobiiliagenttien siirtymist yhdest tietokonej rjestelm st toiseen Agenteilla on tila joka sis lt muuttujat ja funktiot joita tarvitaan agentin suorittamiseen Tila sis lt my s tietoa agentin suorituksen tilasta Tuotteistaminen tarkoittaa tuotteen tekemist helppok ytt iseksi asennusoppaiden konfigurointiskriptien ja loppuk ytt j lle suunnatun dokumentaation avulla T m n ty n tarkoituksena oli valmistella agenttialusta julkaisua varten T m opinn ytety esittelee asennusohjeet agenttialustalle Ty ss on kirjoitettu konfigurointiskripti agenttisovellusten k ytt mien URLien vaihtamista varten Ohjelmointiopas auttaa kokematonta k ytt j kehitt m n mobiiliagenttisovelluksia agenttialustan avulla Julkais
53. lable http ckan org 35 CKAN Docs API Guide WWW Referred 2 10 2014 Available http docs ckan org en latest api index html 36 Snowlake Software Go Publisher Workflow WWW Referred 2 10 2014 Available http www snowflakesoftware com products gopublisher workflow 37 Dspace an open source repository application WWW Referred 3 10 2014 Available http dspace org 38 SourceForge DSpace source code WWW Referred 3 10 2014 Available http sourceforge net projects dspace files DSpace 20Stable 4 2 39 GitHub DSpace source code WWW Referred 3 10 2014 Available https github com DSpace DSpace 62 40 Duraspace DSpace documentation WWW Referred 3 10 2014 Available https wiki duraspace org display DSDOC4x DSpace 4 x Documentation 41 GNU Affero General Public License WWW Referred 8 10 2014 Available http www gnu org licenses agpl 3 0 html 42 Delanghe S Using Learning Styles in Software Documentation IEEE Transactions on Professional Communication Vol 43 no 2 June 2000 pp 201 205 43 Ganier F Factors Affecting the Processing of Procedural Instructions Implications for Document Design IEEE Transactions on Professional Communication Vol 47 no 1 March 2004 pp 15 26 44 Webb Donna R 1989 Writing Effective User Manuals Basic Guidelines and Tips Library Hi Tech Vol 7 no 4 pp 41 47 45 Sommerville I Software Docum
54. meter and provide a reasonable default 5 PRODUCTIZATION 29 e Entities a human such as a system administrator another system or the system itself setting the configuration values need to know what values to set how to set them including formatting and valid values why to set them and their effect on system operation This information should be given in the configuration file not in external document Configuration parameter heuristics according to 27 e Make the configuration parameters easy to change Store them externally in a simple easily managed nonbinary format e Store all of the data in one location e Make configuration data easy to capture and forward to technical support e Make it hard to get the values wrong If they are wrong notify the user as soon as possible and either stop execution or continue with sensible defaults Gather log data while the system is running and offer it to the user Give the user a possibility to turn log data on and off while the system is running System needs to be configured before it begins execution and during its operation It needs to be clear is the configuration parameter used only during initialization or can it be changed while the system is running 5 4 Software productization process Product software is defined in 14 as a packaged configuration of software components or a software based service with auxiliary materials which is released f
55. n L Open Source Licensing Software Freedom and Intellectual Property Law Chapter 10 Choosing an Open Source License WWW Referred 11 11 2014 Available http flylib com books en 4 467 1 1 1 58 Academic Free License WWW Referred 12 11 2014 Available http opensource org licenses AFL 3 0 59 Open Software License WWW Referred 12 11 2014 Available http opensource org licenses OSL 3 0 60 Common Public License WWW Referred 12 11 2014 Available http opensource org licenses cpl1 0 php 61 Hecker F Setting Up Shop The Business of Open Source Software IEEE Software January 1999 pp 45 51 62 Maxwell E Open Standards Open Source and Open Innovation Harnessing the Benefits of Openness Mit Press Journals Innovations 2006 pp 138 141 63 Bilen C C Alavizadeh Z Open Source Strategy A Change of Perception trough the Lens of Innovation Master Thesis within Business Administration March 2011 pp 29 30 41 51 64 The BSD 3 Clause License WWW Referred 14 11 2014 Available http opensource org licenses BSD 3 Clause 65 The GPL License WWW Referred 14 11 2014 Available http opensource org licenses GPL 2 0 66 Krishnamurthy S An Analysis of Open Source Business Models February 2003 WWW Referred 14 11 2014 Available http faculty washington edu sandeep d bazaar pdf 67 Codehaus Licenses Page WWW Referred 17 11 2014 Available ht
56. n both browser and server All computation is implemented in JavaScript and the framework is based on event handlers 6 Navigation model 3 of the HTML5 agent consists of the configuration file that is downloaded with the agent In the current implementation navigation model includes only connections to one agent server and the origin server of the agent Navigation model also includes the serialization and transfer management of the agent Communication model 3 includes communication with the user third party services agent server and another agent application For agent to agent communication there are three cases 3 1 Both agent applications are in separate servers 2 Both agent applications are in agent server 3 One agent is in browser and another is in server Security model 3 relies in standard security mechanisms of HTML5 applications in browser 3 1 3 Architecture Figure 3 3 describes the basic architecture of an HTMLS agent framework and its relationship to application specific implementation Agent part of the architecture consists of a generic agent and an application agent 3 HTML5 MOBILE AGENTS 15 Application Application User Interface Application Agent Framework Server side Generic Agent Execution Environment Figure 3 3 Basic architecture of framework 3 In server the agent can be accessed trough generic interface provided by generic agent In browser the agent can be accessed troug
57. n component listing 7 11 One array for all values is created and another array for counting parameters Then counting parameters are added to parameters array Parameters and results arrays are added to allData array which is passed as a parameter to sendMessage function Listing 7 11 Calling sendMessage function LakeussSrc count js that sendMessage function var allData new Array var parameters new Array parameters push that startValue parameters push that multiplier parameters push that index allData push parameters allData push that results that commComponent sendMessage allData In count html file socket io from agent server must be included because communication component reguires socket io client to be able to work Communication component from file communication js must also be included Files are included as script src values lt script src http localhost 8891 socket io socket io js gt lt script gt lt script src http localhost 8890 communication js gt lt script gt These lines are located between the lt head gt tags in the count html file 7 PROGRAMMING GUIDE 52 7 5 2 Receiving information from Count agent New Receiver agent figure 7 3 is created for receiving results from Count agent Message Receiver Starting value 10 Multiplier 1 2 Number of years 4 Intermediate results 12 000 14 400 17 280 Result 20 736 u
58. n strategies for example migration protocol based on RMI or TCP IP An Aglet 8 9 is a Java agent that can move from host to another and communicate with other aglets In Aglets 1 method run starts the agent Dispatch initiates migration Migration strategy is combination of push and pull strategies In Grasshopper 1 method live starts the agent Move initiates migration When error occurs an exception is thrown Grasshopper uses class loader for pulling and it has no push strategy Agent has a veto right it has a right to vote against migration Transmission aspects Downloading classes from a nearby server is important because shorter distance may improve the time needed for downloading Migration strategies Decision of migration strategy depends on network model structure In homogeneous network pull per unit is a good strategy In heterogeneous network it is useful to push code in most cases 1 2 1 4 Kalong mobility model Kalong 1 allows agent or it s programmer to define new migration strategies How Kalong differs from current mobility models e 1 Agents have an external state and code is transmitted in code units e 2 It has code server agency and mirror agency e 3 It has new class cache mechanism it can prevent class downloading or code transmission Kalong s functions to get and set data of external state are getData and setData If sender agency is remote agency all data of external state is transferred with agent s
59. o do in defined intervals Generic agent has no implementation of work function 7 PROGRAMMING GUIDE 43 3 7 1 2 setWork name of work function Sets the defined work function for the agent Enables the use of other function name than work Changing work function during the agent execution is possible start Starts agent stop Stops agent execution getRunning Status Gives the status information of agent Used when agent is in server isInServer Returns true if agent is in server otherwise returns false Variables In order to get the agent state private variables and functions are assigned to members of that 32 that is a variable where all the functions and variables that application agent has access should be saved 7 2 src contains URL to JavaScript file functionality of the application Src can be an array of URLs to the JavaScript files if the agent consists of multiple files html contains URL to the html file user interface of the application which has references to CSS files and other needed files like image files 3 Application agent Application agent 3 is a concrete implementation of an application that can travel between browser and server Application agent s variable that should include all variables that are saved to memory so generic agent can find them 7 2 1 7 2 2 Compulsory functions for application agent work Things agent needs to do to update it s state fo
60. o license contract document and usage rights description document 4 7 2 Comparing AVAA and IDA with data management systems Compared to other data management systems introduced in section 4 5 IDA has clear instructions for applying user permits Whereas DSpace is suitable for commercial organizations AVAA is more directed for the use of research organizations like universities CKAN s 34 JSON api is used for adding and editing data and in AVAA the numerical data can be retrieved in JSON format AVAA and CKAN are both aimed at data publishers wanting to make their data open and available They also offer tools to analyze and visualize data as well as license information If the data that is published via AVAA is stored via IDA then there is the same ability to store metadata that is also available in DSpace and CKAN 4 8 Proposal for license and publishing platform License for HTML5 agent framework should be a copyleft license like GPL 3 0 or AGPL 3 0 These licenses ensure that the software stays open and other developers can make improvements to the framework and develop new applications Licenses are also well known high guality and revisions from previous versions of themselves For publishing place GitHub would be suitable if there is also need to host a project where framework is further developed GitHub is very popular with over eight million users and over nineteen million repositories 77 If there is no need for project host
61. ocessing 2010 Vol 51 pp 90 102 13 Meyer M H Seliger R Product platforms in software development Sloan Management Review vol 40 1998 pp 61 74 14 Xu L Brinkkemper S Concepts of product software European Journal of Information Systems vol 16 no 5 Oct 2007 pp 531 541 15 SourceForge WWW Referred 9 8 2014 Available http sourceforge net 16 Lauchpad WWW Referred 9 8 2014 Available https help launchpad net Projects FileDownloads Publishing files 17 Open Source Licenses WWW Referred 10 8 2014 Available http opensource org licenses 18 Choosing Open Source License WWW Referred 11 8 2014 Available http choosealicense com licenses 19 GitHub help Open Source Licensing WWW Referred 11 8 2014 Available https help github com articles open source licensing 20 GitHub help Support for subversion clients WWW Referred 11 8 2014 Available https help github com articles support for subversion clients 21 Launchpad software collaboration platform WWW Referred 11 8 2014 Available https launchpad net 22 Google Project Hosting WWW Referred 12 8 2014 Available https code google com projecthosting 23 BitBucket WWW Referred 12 8 2014 Available https bitbucket org features 24 Codehaus WWW Referred 12 8 2014 Available http www codehaus org 25 YoLinux com Software Productization Software Archi
62. onal software packages and can be started out of the box Radigost relies on web workers and web sockets Web workers enable multi threading and asynchronous messaging which means that no timers or scheduling are needed Radigost agents interact with host environment trough message exchange or included listener object Radigost supports reactive architecture agent behavior is based on messages received from the environment or other agents Each agent has a globally unigue identifier AID which is a string value Agents have a state that can be serialized into JSON string Radigost is interoperable Radigost agent can interact with other agents in third party multi agent platforms Radigost s runtime performance has been evaluated with several case studies 2 2 2 Telescript Telescript programming language 10 is designed for development of mobile agent programs In Telescript places are processes that are inhabited by agents Telescript agent needs a ticket containing address of the place to move from place to another Ticket also contains definition of how the agent will travel like the communication protocol Agents can communicate with each other in meetings To meet another agent a valid petition has to be presented by the agent initiating the meeting Agents can be 2 MOBILE AGENTS 8 created and accessed by submitting special HTML forms or following hyperlinks Migration is initiated with go command 2 2 3 Grasshopper Grasshopper 28
63. or and traded in a specific market In 12 productization is defined as a transformation process from developing customer specific software to product software Software productization process introduced in 12 consists of six different stages see figure 5 1 6a i Customizable 1 Man 3 4 5 product Independent as Product p Product p Product projects h recognition basis Platform projects 6b Standard product Figure 5 1 Software productization process 12 5 PRODUCTIZATION 30 In stage 1 company has independent customer driven projects producing software applications In stage 2 features or functionalities are reused across projects Projects use standardized features but the amount of developed customized features is still larger In stage 3 the standardized part of the projects is larger than the customized part This stage is called product recognition first step of creating a product Storing and managing customer requirements in one central place is important because satisfying customers is the main focus of this stage In stage 4 product is recognized and product platform is used as a basis The focus of satisfying the customers is decreasing and the focus of gaining more market share is increasing Stage 5 is called standardizing product platform increasing the set of features that form a common structure and introduce releases from which still a stream of derivate products can be effici
64. piled binary form and do not require access to source code BSD licenses 26 64 are very permissive licenses Unlike the GPL BSD licenses allow proprietary products to be built and sold from the BSD code without requiring that the source code be given away BSD licenses are generally GPL compatible The Artistic License Perl 26 has several differences compared to the Apache license The Artistic license allows changes to the source code if e User makes these changes in public domain e Or user uses only modified code within a company or organization e Or user renames modified code so that it doesn t conflict with the standard version The Artistic License is GPL compatible In Mozilla Public License MPL 26 modifications must be made freely available to the developer community This resembles to the GPL Larger pieces of software are not required to make source code available Developers can improve the open source code base without giving away their own property This differs from the GPL MPL is not GPL compatible on its own but there is an effort to relicense all Mozilla code under a triple license with the GPL and LGPL Dual licensing 26 means that sellers offer option of choosing either a GPL option or more conventional commercial license 4 2 Choosing a license In 53 choosing a license is decided based on whether the user wants a copyleft license or non copyleft license Recommended copyleft licenses are the GPL 3 0 54 o
65. pload Figure 7 3 Message receiver user interface When creating new communication component listing 7 12 callback function is given as a parameter Inside callback function the received message is stored to local msg variable and shown in console and user interface When receiver agent is at server received result is shown as a running status Listing 7 12 Creating communication component LakeusSrc receiver js that commComponent new CommComponent function message that msg message console log message that updateView 1 that commComponent setNameSpace count that commComponent initIO 7 PROGRAMMING GUIDE 53 Setting namespace and initializing connection are done same way as in Count agent constructor Namespace must be the same as the namespace set to Count agent so it is set to count 8 EVALUATION 54 8 EVALUATION This chapter contains an evaluation of installation and programming guides based on installation and configuration principles and general user manual and technical writing guidelines According to 27 the most useful form of documentation for beginner and intermediate level users is a step by step tutorial of how to get a project running This principle has been followed in chapter 6 and 7 by writing them in tutorial form Things that entities a human such as a system administrator another system or the system itself setting the configuration values mus
66. r example guery data If work function should be changed agent must be stopped before setWork call and started after setWork is called continueWork Initializes or resets application specific parts that are not saved in memory or variable list of an agent E g Values of drop down menus in browser Also setRunInterval and start functions of the generic agent should be called in this function 3 Additional compulsory functions for application agent CreateAgentObject location of the javascript and html files of the agent is a factory method that creates agent application object without including 7 PROGRAMMING GUIDE 44 application specific code to the agent server This function is needed in both browser and server e InitExecution is called in HTML body agent is initialized and started before UI is shown to the user using onLoad function 3 7 3 Creating an example agent application When starting to create an application agent general guidelines introduced in 3 section 5 1 should be followed This tutorial explains the steps of creating a simple agent application that increases index on each call of work function Functionality of the application is written in index countjs file and user interface of the application in index count html file Listing 7 1 shows the first steps in creating a constructor Variable that and a new instance of Agent class are created Application variable index is initialized and sa
67. r the AGPL 3 0 41 If granting patent rights from contributors to users is important recommended non copyleft license is Apache 2 0 55 If not MIT is very permissive 4 OPEN SOURCE 20 and simple as well as BSD Apache MIT and BSD licenses are proprietary compatible licenses they allow the covered code to be used in proprietary programs All these licenses are widely used and well recognized People don t have to read the legalese in order to use the code because they have already done that It is easier for people to entry for this kind of project Licenses are high quality and revisions of previous versions of themselves 53 According to Rosen 57 for commercial companies the discussion of which open source license to use often centers one or both of following issues 1 How can we make money from distributing this software under an open source license In essence can our license help us sell free software 2 How can we prevent others from making money unfairly from our open source software This is the so called free rider issue where licenses reap all the benefits of others work with no return obligations 4 2 1 Making money from Open Source Customers are often willing to pay for brand name software 57 particularly if it comes with support and other benefits Names and reputations of the licensors are excluded from several open source licenses Licensors can protect their names and reputations for personal profit
68. ration means transferring mobile agent from one computer system to another As compared to the client server applications migration saves network bandwidth by moving the code close to the data Mobile agent is executed as part of the mobile agent 2 MOBILE AGENTS 4 server software It controls execution of agents and provides functionality for agent communication agent control security and migration In Mobile Agents book 1 mobile agent server is called agency Agency that holds the agent s code is code server which usually is the home agency Mobile agents consist of code data variables and execution state Mobile Agents book names current agency as sender agency S and other agency as receiver agency R The migration protocol defined in the book has six steps see the figure 2 1 Sender Receiver Initialize migration Start agent execution process Capture data and state Deserialize the agent I Receive the agent Transfer the agent Network Figure 2 1 Migration process 1 e SI Suspend the execution thread initialize the migration process e S2 Capture agent s data and execution state Serialization of the current state of all variables Current values are written to an external persistent representation which can be a memory block or a file Agent s state is stored in same place Outcome is a serialized agent a flat byte stream
69. rialized object Method name to invoke at destination and classes that agent might ever use are transferred to the receiver agency Redundant classes are deleted from the code closure before the byte code is collected Code closure consists of the agent s main class and all the classes that are used for variables method parameters method return values and all local variables of any class of the code closure Class is searched in the agent s code base which is defined when launching an agent All class files are already at the destination agency so class loader has to look for the byte code only in a local repository where the incoming classes are stored 2 3 Communication Example case where agent communication 1 is needed is an application in which agent arranges a business trip for a human user Slave agents are specialized agents to find information about flights hotels etc These specialized agents are instructed by 2 MOBILE AGENTS 9 master agent that communicates to the user and monitors the entire process All these agents exchange information about their tasks and intermediate results The main problem in getting mobile agents to communicate with each other is how to locate agents that can move autonomously in network Locating is important so that agent s task can be modified and send a termination signal when its has become obsolete It must be possible to detect agents that are orphans to avoid unnecessarily consuming of resour
70. rted These things haven t been done much in this project Although the repository is public it was meant to be used inside the project 4 7 AVAA open access publishing platform AVAA 68 is presented here as one possible publishing place for open source data AVAA is an open access publishing platform where users such as research groups can suggest their own web applications or web page presentations found on the server of their own organization for publication in the application gallery The purpose of AVAA 69 is to offer a platform and web based tools for different disciplines to enhance accessability of open data AVAA portal includes e Interfaces and download functionalities for distributing research data e Applications for analyzing and visualizing data Data that is published via AVAA 69 can be stored to IDA Storage Service 70 or on the data provider s or owner s own servers Data and applications page lists links to research data and applications The current applications in AVAA 68 are from different disciplines for example atmospheric sciences geosciences and language research With these applications user can for example download atmospheric data study spreading of pollution clouds on a map or use OpenStreetMap application trough interface service For Geosciences OpenStreetMap application 71 there is also a link for downloading a zip package There are also links to map images in several formats including W
71. s file All modified files are listed and modifications are explained in listing 9 2 Listing 9 2 Modified files Filename Modifications Purpose of modifications agentserver handlers js Included communication Getting agent to agent component variable communication working 9 CONCLUSIONS 57 when one of the agents is uploaded to agent server configuration js Added new parsePort Getting server port directly function that parses agent from configuration URL file or load server ports from configuration URLs configuration js Added new serverPort Functions that agent file functions to get agent and load servers can call to file or load server ports get the port number from from configuration file configuration URL agentserver js Calls agentserverPort Removed hard coded function of configuration agentserver port number file to get the port directly Agentserver port must be from configuration URL changed only to configuration file fileserver js Calls fileserverPort Removed hard coded function of configuration fileserver port number file to get the port directly Fileserver port must be from configuration URL changed only to configuration file loadserver js Calls loadserverPort of Remover hard coded configuration file to get the loadserver port number port number directly from Loadserver port must be configuration URL changed only to configuration file
72. st1 port1 Listing 6 2 Concrete example of modified values LakeusSrc configuration js this listUrl function return http localhost 8891 list this uploadUrl function return http localhost 8891 upload this loadavUrl function return http localhost 8892 this applicationUrl function return http localhost 8890 If you want to test installation with an example gmonitor application edit script src value in gmonitor html Modifiable parts are shown in listing 6 3 and concrete example values in listing 6 4 Listing 6 3 Highlighting the modifiable parts of URL LakeusSrc gmonitor html lt script src http myhost2 port2 configuration js gt lt script gt Listing 6 4 Concrete example value LakeusSrc gmonitor html lt script src http localhost 8890 configuration js gt lt script gt Change the original host and port of the URL so that they match the host and port of your application server This ensures that the gmonitor application running on browser can get the configuration js file 6 INSTALLATION GUIDE 34 6 4 Node js installation Because servers have been implemented with node js it must be installed before servers can be started Open new terminal window Easiest way to open a new terminal window is to press Ctrl Alt T To install nodejs manually do following steps 4 1 Install nodejs
73. state JoadData and uploadData are functions for loading and uploading data item of an external state from to home agency Kalong model makes possible less transmission of data items and code It also increases security agent can leave important data items to the home agency until they are needed A code unit consist of at least one Java class a JAR file Code base is the 2 MOBILE AGENTS 7 place where unit can be loaded Two agents can have different code units even if they belong to the same type Things that must be known to be able to download code 1 To which code unit does the class belong 2 From which code base the code unit should be loaded Migration process The parts in which the agent is transmitted are 1 State 2 Code units Java class files Types of agencies e Code server agency Some code units will be stored at the current agency e Mirror agency Keeps information about code and data can take the role of the home agency Code cache Basis of classes technigue digests or hash values to check whether two classes are egual Prevents transmission of identical code units When the agent terminates it has to release all code servers to free resources 2 2 Examples of Mobile Agent platforms 2 2 1 Radigost Radigost 2 is a multi agent platform executed inside of the client s web browser Radigost is mostly developed in JavaScript and doesn t reguire third party plug ins like Java or Adobe Flash It reguires no additi
74. stent process based life cycle is described in figure 3 1 save inner state retrieve inner state Figure 3 1 Persistent process based life cycle 56 3 Life cycle 56 3 starts with a start state where the agent is started for the first time Then the agent is moved to a running state where a persistent process is executed Before the migration from one host to another the inner state of the agent is saved and the agent enters the frozen state After the migration the inner state of the agent is retrieved and the agent continues execution in the running state at the point where it left off After the execution is finished the agent enters a death state where the process is terminated Computational model 56 describes how the execution of a mobile agent occurs when the mobile agent is in running state 3 HTML5 MOBILE AGENTS 13 Security model can be split into two areas Protection of hosts from destructive mobile agents and protection of mobile agents from destructive hosts Communication model According to 6 Communication model defines means to communicate with the environment and other agents Navigation model 56 discovers all aspects of agent mobility from discovery and resolution of destination hosts to the manner in which the mobile agent is transported 3 1 2 HTML5 agents and mobile agent models HTML5 agent 3 needs the models for the mobile agent Agent life cycle and computational models have complete implem
75. t hl gt Index Count lt hl gt lt div style height 20px gt lt div gt Index lt span id index value index gt lt span gt lt div style height 40px gt lt div gt lt input type button onclick agent upload value upload gt lt body gt lt html gt In the head tag configuration js file is first downloaded from application server and then index count js file is downloaded using downloadAgent function in the configuration file Agent execution is started by calling initExecution function When user presses upload button the upload function of the agent is called and agent is sent to the agent server 7 4 Adding new values and functions to Count agent Second example is build using index_count js file as a basis of both agent applications Purpose of this example is to show how agent to agent communication works Application that counts compound interest is created see figure 7 2 It multiplies the starting value with a certain multiplier and continues to multiply the result value of previous count on each execution of work function Counting is done in phases because intermediate results are stored and shown to user In section 7 5 communication component is added to counting application for sending the counting results to receiver agent which receives the counting results and shows them to user Application codes are written in count js and receiver js files and user interfaces in count html and receiv
76. t know are 27 e What values they can set e how they can set the values e why they have to set the values e and how the values effect on system operation Installation guide s section 6 3 explains user what kind of URLs there are and what is their purpose Then an example is shown where the configuration URLs are changed directly to the configuration file From the installation principles described in section 5 2 only the one that advices to provide information about installation process to the user realizes because node js installation informs user what is being done by printing information to the terminal window From the postinstallation configuration principles the one that tells to execute installed software realizes because in the installation guide the user is advised to test the installation of the agent framework with an example gmonitor application Following the configuration parameter heuristics described in chapter 5 2 the configuration parameters have been made easy to change by providing a configuration script for changing the URL values from command line If user enters empty line previous URL is stored to configuration file This configuration script is only meant to be used before the system is running Scripts that enable configuration changes while the system is running could also be made Graphical user interface for changing configuration or ability to easily change configuration files by defining agent manifest fil
77. tecture and Design for Productization Description of software architecture design and concepts to support 61 software productization WWW Referred 7 9 2014 Available http www yolinux com TUTORIALS SoftwareArchitecture Productization html 26 Woods D Guliani G Open Source for the Enterprise Managing Risks Reaping Rewards O Reilly Media 2005 p 9 21 72 pp 29 44 105 126 27 Hohmann L Beyond Software Architecture Creating and Sustaining Winning Solutions Addison Wesley Professional 2003 pp 203 234 28 An Overview of the Grasshopper Agent Platform WWW Referred 24 9 2014 Available http cordis europa eu infowin acts analysys products thematic agents ch4 ch4 htm 2 29 Node js WWW Referred 25 9 2014 Available http nodejs org 30 Socket io WWW Referred 25 9 2014 Available http socket 1o 31 Inversion of Control Containers and the Dependency Injection Pattern WWW Referred 26 9 2014 Available http martinfowler com articles injection html 32 Crockford D Javascript The Good Parts O Reilly Media Inc 2008 172 p 33 Carzaniga A Picco G P Vigna G 1997 Designing distributed applications with mobile code paradigms In Proceeding of the 19th international conference on Software engineering ICSE 97 May 17 23 1997 Boston Massachusetts USA pp 22 32 34 CKAN The open source data portal software WWW Referred 2 10 2014 Avai
78. tp www codehaus org customs licenses html 68 AVAA open access publishing platform WWW Referred 18 11 2014 Available https www tdata fi avaa 69 AVAA Pilot portal WWW Referred 18 11 2014 Available http avaa tdata fi web avaa etusivu p p id 56 INSTANCE WnrBJ3tLtuRh amp p p lifecycle 0 amp p p state normal amp p p m ode view amp p p col id column 64 1 amp p p col count 1 amp 56 INSTANCE WnrBJ3tLtuRh languageld en US 70 IDA Storage Service WWW Referred 18 11 2014 Available https www tdata fi ida 71 AVAA Data amp applications Geosciences WWW Referred 18 11 2014 Available http avaa tdata fi web avaa geotieteet 72 WebDAV WWW Referred 18 11 2014 Available http www webdav org 73 CSC IT Center for Science WWW Referred 19 11 2014 Available https www csc fi home 74 iRODS The Integrated Rule Oriented Data System WWW Referred 19 11 2014 Available https irods org 75 CoRed Collaborative Coding in the Web for the Web WWW Referred 26 11 2014 Available http cored cs tut fi 76 GitHub CoRed Source Code WWW Referred 26 11 2014 Available https github com ahn cored 77 GitHub Press Page WWW Referred 4 2 2014 Available https github com about press
79. un helpottamiseksi open source lisensseihin ohjelmistojen is nn intipalveluihin ja tiedonhallintaj rjestelmiin on tutustuttu IV PREFACE I started to study the agent platform on spring 2014 I began by studying mobile agents and reading the agent platform code I wrote installation guide mostly in June Programming guide configuration script and configuration file modifications were done in autumn I want to thank my supervisor Kari Syst for reading and commenting the thesis and giving technical guidance In Tampere on the 5th of February 2015 Sami Turunen INDEX 1 EQOA IC LOM ansa jansa ehka se OTA SAK soc so tepals aga gine ovina dae lve asap aides wh en 1 2 Mobile Agents sun vaa oe a e E E E ends E RE E ETS 2 2 1 General information about Mobile Agents s sesseseseessesssesressrssreserrsssressee 2 DMM ODIN SSS tenenu a a aku a a de 2 212 Miga OMen ee rea ar sak nad Ea aaa En ARTA EAE CENA EEEE 3 2 1 3 Mobility models of Aglets and Grasshoppet c ccccecseseeeeeeeees 5 2 1 4 Kalong mobility modelu sauva mmasasa cessatebanteteaevisoanstatscorecennmncnecens 6 2 2 Examples of Mobile Agent platforms uouusssnsn naa n naa eeeeeen 7 ZAI RAATS OS mama asa Ts STELK s a A T E E 7 2 22 SIGS esis n a dey casino hea 7 22 9 SATASSHOP Pel maamassa eaceteueeta ols h asansead acne eeiassnak eos 8 DOA Tracy 1001 ss cosshicstt cg ae SA um mata tn ano mik s Tan Aaa bet ees 8 23 CCOMMAUMICATI
80. ved to the memory of the agent with register Var function Listing 7 1 Initializing and registering the agent variables LakeusSrc index_count js function Count src html 1 var that new Agent src html that index 0 that registerVar index In second step listing 7 2 application specific continue Work function is extented to variable that continueWork is used for initializing the agent Interval for the calls of work function is set in restartWork function Listing 7 2 Extending continue work function LakeusSrc index_count js var agentContinueWork that continueWork that restartWork function this setRuninterval 4000 7 PROGRAMMING GUIDE 45 Function work listing 7 3 for increasing the index is extended to variable that In work function index is increased and printed Listing 7 3 work function LakeusSrc index_count js that work function that index that index 1 document getElementById index innerHTML that index console log Index that index Application uses the same upload function that is defined in Agent js file Upload function is used for serializing agent state and sending it to server Variable that is returned in the end of constructor After creating a constructor separate createAgentObject function is created for creating new Count agent Function is showed in listing 7 4 Listing 7 4 Creating new
81. wner Itinerant agents search network efficiently by moving in network to service or information provider Agents can work asynchronously while the user is offline Agent reports results of its work to user trough different communication channels It can suspend execution on arbitrary point and transfer itself to another computer system This is called migration At destination computer system agent s execution is resumed Mobile agents can be considered as additional design paradigm supplement of traditional technigues Mobile agents e Are used in wide area and heterogeneous networks where assumptions of reliability of computers or security of network can t be made e Migration is initiated by agent or the programmer of agent not operating system or middleware e Migration is done to access resources available only at other servers e Can migrate more than once This is called multi hop ability 2 MOBILE AGENTS 3 State means information about the execution state of the agent The execution state can be information from within the underlying virtual machine about call stack register values and instruction pointers Agent server or agency means execution environment for agents Agency e Provides agents services communication and migration to other agencies e Controls execution of agents and protects against malicious agents A mobile agent toolkit 1 is a specific project or product Examples of mobile agent toolkits are IBM a
82. xed 3 that index that index 1 Work function listing 7 9 calls multiply fuction for counting update View function for showing results in browser and sendMessage function to send result values Listing 7 9 Work function for Count agent LakeusSrc count js work function that calls multiply for counting and sendMessage for sending the results that work function that multiply Show results in browser that updateView For server to show results console log that result console log that results slice 0 that results length 1 Sends message to another agent that sendMessage 7 PROGRAMMING GUIDE 50 gt When the agent is uploaded to server counting index is shown as a running status 7 5 Getting the communication working Currently it seems that the working version of socket io npm package is 0 9 4 Open terminal window Install socket io and socket io client sudo npm install socket io 0 9 4 sudo npm install socket io client 0 9 4 When the agent server is started from terminal text socket io started should be shown CommunicationUrl in configuration js file should be set as http myhost myport where myhost is the hostname of your agentserver and myport is the port number of your agentserver In this example the communicationUrl is http localhost 8891 CommunicationUrl must be configured to ensure that the communicat
83. y installation and configuration principles during productization A software productization process was also briefly described Main purpose of this work was to prepare a mobile agent platform for publishing by writing an installation and a programming guide for the platform Open source licenses were studied as well as open source software hosting facilities and data management systems Productization in this thesis included installing the agent platform Unpacking code installing nodejs and npm modules and configuring URL values in configuration file These steps were then documented to the installation guide Starting agent servers and installation testing with an example gmonitor application were explained A script for node js installation was made as well as a script for changing URLs easily from command line Script files are described in listing 9 1 Listing 9 1 Script files Filename Purpose of file nodejs install sh Installs node js Installs mime and socket io modules to node js change urls sh User can modify configuration URLs from command line and changes are made directly to the configuration file New functions were added to the configuration file to offer port numbers of servers directly from the configuration file instead of having hard coded port number values in each server file Server files were modified to call these functions Communication component variable was included to agentserver handlers j

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