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MASTER`S THESIS - Department of Telematics

1. 45 6 3 2 Internal is 47 6 3 3 uae 49 7 DTS CUSSION ROT E N T AET T N E EN 52 7 1 ARCHITECHURES A I 52 7 2 E 54 7 3 je Da E10 E t h ANE E AEE E ET 59 7 4 PERFORMANCE TERES EE 55 7 5 M 56 7 6 SYSTEM INTERFACE CONSIDERATIONS ccsssscsccccecsssscececececsesseaececececseseeaececececsessaaececececsensaaeeeeececeenes 57 7 1 FUTURE WORK 355 52 57 8 59 REFERENCES e 60 APPENDIX A IMPLEMENTATION 61 61 2 ee 64 jai dudes EE 65 4 3 1 ES E EAA EA be 66 NAMEN T ERR Tem 69 APPENDIX B USER 72 1 PD LES 72 B 2 IMOBIEEJPHONE Oti SUR RUDI eT ET 72 APPEN
2. cles det ee dde donde 19 EIGURES I SYSTEM OVERVIEW Sie Pees ey 26 FIGURE 5 2 XML REPRESENTATION OF A eene rennen enne nenne tenir ertet sensns nnns 28 FIGURE 3 3 WAP EFRONTMENU eui de pertes ue eere pe ede he 33 FIGURE 5 4 SCREEN PHOTOS OF CONTACT INTERFACES ener enne 33 FIGURE 5 5 SCREEN PHOTOS OF EVENT INTERFACES 1 2 enne ennt ener nnns 35 FIGURE 6 1 ROLE DECOMPOSITION OF THE RETAILER 4 44 14 rennen 44 FIGURE 6 2 BUSINESS RELATIONSHIPS i n E E ERG REI ED REGERE I EHE HERR eR ATTE Geers 45 FIGURE 6 3 SERVICE REALIZED IN AN INTERNAL NETWORK 46 FIGURE 6 4 RETAILER AND CUSTOMER ROLES FOR THE INTERNAL NETWORK SCENARIO 46 FIGURE 6 5 RETAILER CUSTOMER AND THIRD PARTY ROLES FOR THE INTERNAL SERVICE SCENARIO 48 FIGURE 6 6 RETAILER AND CUSTOMER ROLES FOR THE PUBLIC SERVICE SCENARIO eene 50 FIGURE 7 1 TARGET ADDRESS FILTERING 54 FIGURE 1 VIEWSEARCHRESULTS METHOD 5 iste eH ER e Ee ERR E
3. data synchronization and storage Master s thesis by Bent Erik Skogstad E SyncConnector Exchange 1 2 SyncConnector Exchange Exchange Contact SyncSource exchang Edit Exchange SyncSource Source URI Exchange folder Name Type Host Port Supported types Encoded Conversion type Supported versions Jexchange contacts exchanae contacts exchange contacts texth vcard exchange pats no 80 textx vcard textivcard vCard SyncConnector Exchange 1 2 SyncConnector Exchange Exchange Contact SyncSource Jexchange contacts SyncConnector Exchange 1 2 SyncConnector Exchange Figure C 1 Exchange Contact SyncSource Exchange Calendar SyncSource alae Edit Exchange SyncSource Source URI Exchange folder Name Type Host Port Supported types Encoded Conversion type Supported versions Jexchange calendar exchange calendar texth vcalendar exchange pats no 80 1 0 SyncConnector Exchange 1 2 SyncConnector Exchange Exchange Calendar SyncSource Jexchange calendar Figure C 2 Exchange Calendar SyncSource Note The configurations in Figure C 1 and Figure C 2 are va
4. 23 TABLE 4 5 LIST OF REQUIREMENTS EUER EINER SEDE 24 TABLE 5 1 CONTACT FIELDS FOR ADD CONTACT INTERFACE cccsssccesssscecssssececesseeceessscecseaeeecseaeeeecsseeeesssareeeesaes 30 TABLE 5 2 INPUT FIELDS FOR WAP CONTACT INTERFACES 0 cccsssscceessssecssseeeecssseececseseecseseeeecesseeeesssnseesesarsessees 34 TABLE 5 3 INPUT FIELDS FOR WAP EVENT INTERFACES 36 TABLE 5 4 CONTACT TEST SCENARIOS ii torte e cetero tede ove ete pete de deed iia 37 TABLE 3252 EVENT TEST SCENARIOS ee Hes tue eeu 38 TABLE 3 0 SYNCHRONIZATION SCENARIOS Fore etu esed crib duc boue ga ede 39 TABLE 3 7 SUMMARY OF TEST RESULTS even d Hd EUER 41 TABLE 7 1 SYNCHRONIZATION TIME CONSUMPTION eret eset EKE ea EESE E 56 FIEES aciei rer e recreate er Ree e o rers da epe ec RR Eg 63 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Abbreviations CGI DS DTD GPRS GUID HTTP HTTPS IMEI ISP JSP LUID MRS OMA PDA PIM SLA SWOT SyncML WebDAV WLAN WML URI XML Common Gateway Interface Data Synchronization Document Type Definition General Packet Radio Service Gl
5. lt postfield name query_fullname value query fullname gt lt postfield name query_org value query org gt lt postfield name query_dep value query dep gt lt postfield name query title value query title gt lt postfield name query role value query role gt lt postfield name query_tel value query_tel gt lt postfield name query_fulladdress value query fulladdress gt lt postfield name task value task gt lt postfield name main value main gt lt postfield name item value lt System currentTimeMillis gt gt lt postfield name db value lt c out value param db gt gt lt go gt lt anchor gt lt p gt lt do label Tilbake type prev gt lt prev gt lt do gt lt card gt lt wml gt Figure A 4 WML card included in search jsp Contact search A 3 Screenshots This chapter includes screenshots of various web user interfaces Screenshots for contacts and events are included Figure A 5 shows the front menu 65 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Mobile Repository System Mozilla Firefox DER Ele Edt view Go Bookmarks Tools Help PE an 22 E O 9 htepsiit29 241 219 132 pimweb menu jsp v Q Telenor Mobile Repository System telenor Contact search Add contact
6. ee orb 15 3 2 THE SYNCAIPROIEGCT retiro is rr EO aR SEESE Ee E 15 2 24 SNCI SVCSeFVOF vocis eoe tte WERE E EAE E E 16 2 2 2 Execution 17 3 3 THE NVCARD IFORMAT 18 3 4 THE ICALENDAR FORMAT 19 4 REQUIREMENTS 20 4 1 SCENARIOS PL 20 Ald Lossofmobile phones ai one e ee hatha eet 20 412 Contact list lookup ausos eee basis eve oie gre eA 21 LLI NewcontactinformalOn Ori Un QU e E RUN 22 Zl Calendar appointment oc ioi Duae DINING HR UR I eae eee 22 4 2 TDISPORREOUIBENENES iuter dde 23 gt SYSTEM DESCRIPTION 25 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad 5 1 SYSTEM OVER VIEW MEC C 25 5 2 Gasse eintreten nti vin netta attt 26 SI Syn Connector Exchange ete pie et to ee 27 5 2 2 Anthenea oM secat Dni ptite nne
7. 2 40404041 2 000000000100000000000000000004000000000000000 76 FIGURE C 2 EXCHANGE CALENDAR 5 2 2 4 142 00 000 00000000000000000000000000800000 innen 76 iv MRS Mobile Repository System data synchronization and storage Master s thesis by Bent Erik Skogstad List of tables TTABEE2 I CUID GUID MAPPING 2322 Ee ento e eei 3 TABLE 2 2 EXAMPLE DATABASE CHANGE TABLE sccssssscecssssecesssnsecsensnsesssceececsessecsessssesssneeeecesnsessessnsesssseseessensess 4 TABLE 2 3 SYNCHRONIZATION MATRIX 74er cava 5 1 5 6 17 TABLE 3 2 VCARD INFORMATION e 18 TABLE 4 1 USE CASE 1 TRANSFER CONTACT LIST TO NEW 4 2 0 0002094401 0 0006 00000000008 20 TABLE 4 2 USE CASE 2 CONTACT LIST LOOKUP ss rb e Ee E de ace ris P eiie ce 21 TABLE 4 3 USE CASE 3 NEW CONTACT 2 enne nennen ener tenen nennt enne 22 TABLE 4 4 USE CASE 4 ADD NEW APPOINTMENT INVOLVING OTHER 0
8. END VEVENT END VCALENDAR Figure 3 9 Example iCalendar UID Unique Identifier This property defines the persistent globally unique identifier for the event 9 19 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad 4 Requirements This chapter presents some scenarios that illustrate synchronization needs and also the use of storing central company data Not all desired features described in the scenarios are implemented but the scenarios are still included to present ideas for future work that could be useful The main purpose of describing scenarios is to gather system requirements and these will be presented for each scenario and summarized formally at the end of the chapter 4 1 Scenarios Scenarios are first given to illustrate followed by a textual use case description that describes the flow of actions needed to realize the scenario These scenarios will yield a number of requirements to the system 4 1 1 Loss of mobile phone Mary was on holidays in southern Norway and was unfortunate enough to lose her mobile phone in the water For a while she had planned to buy a new phone so she was not very upset After she bought the new phone she realized that she also had lost her entire contact list Luckily Mary was a Telenor customer and had her list of contacts stored on a central server The only thing she had to do was to synchron
9. and all of these words must be substrings of the corresponding fields in the database Figure A 1 shows an excerpt of the method viewSearchResults 261 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad for int 150 i lt size i HashMap item getCalendar files i StringTokenizer querysumm new StringTokenizer String request getParameter query PARAM SUMM toLowerCase StringTokenizer querylocation new StringTokenizer String request getParameter query PARAM LOCATION toLowerCase boolean match true while querylocation hasMoreTokens if location toLowerCase indexOf querylocation nextToken 1 match false break else match true if match while querysumm hasMoreTokens if summ toLowerCase indexOf querysumm nextToken 1 match false break else match true Figure A 1 viewSearchResults method Each file in the respective folder contacts calendar is being checked for its contents for loop In the method excerpt in Figure A 1 the entered strings in the summary and location fields are tokenized and each token is compared to the corresponding content of each of the files in the database If one of the tokens is not a substring match is set to false and the next item in the for loop is checked If match remains true at the end of the for loop the curren
10. gt lt Connector port 80 3 Inc Program FilesNSync4jNsyncserver 4 0 8NconfigNSync4j properties change the server address server uri http 129 241 219 132 sync4j sync 4 In C Files Sync43 syncserver 4 0 8 install properties change the server address server name http 129 241 219 132 sync4j sync Add Exchange module 5 Download and unzip SyncConnector Exchange 1 2 4 available from http sync4j funambol com main jsp mainzdownload stable The file is also available on the enclosed CD install syncconnector exchange 1 2 4 zip 6 Copy syncconnector exchange 1 2 s4j to syncserver 4 0 8 modules 7 In C Files MSync4jNsyncserver 4 0 8Ninstall properties add Exchange modules to the list of modules to install modules to install foundation 1 5 1 pdi 1 3 pimweb 1 1 1 syncconnector exchange 1 2 74 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Reinstall SyncServer 8 9 10 11 Start the Sync4j server Start gt Programs gt Sync4j gt SyncServer gt Start Open a command shell and set the relevant environment variables SET J2EE_HOME C Program Files Sync4j tools tomcat SET JAVA HOME C Vj2sdk1 4 2 05 or similar Change the command line path to c Program Files Sync4j syncserver 4 0 8 Type bin install tomcat50 to re install the SyncServer 12 Re start the SyncServer
11. with the server R4 1a The user shall be able to modify a contact item in MRS using a OK 4 mobile phone R4 1b The user shall be able to modify a calendar item in MRS using OK T10c a mobile phone R4 2a The user shall be able to modify a contact item in MRS using a OK T4b PDA R4 2b The user shall be able to modify a calendar item in MRS using OK T10b PDA R4 3a The user shall be able to modify a contact item in MRS using a OK T4a computer R4 3b The user shall be able to modify a calendar item in MRS using OK T10a a computer R5 1a The user shall be able to add a contact item to the MRS using a OK T6c mobile phone R5 1b The user shall be able to add a calendar item to the MRS using OK T12c a mobile phone R5 2a The user shall be able to add a contact item to the MRS using a OK T6b PDA R5 2b The user shall be able to add a calendar item to the MRS using OK T12b a PDA R5 3a The user shall be able to add a contact item to the MRS using a OK T6a computer 41 MRS Mobile Repository System data synchronization and storage Master s thesis by Bent Erik Skogstad R5 3b The user shall be able to add a calendar item to the MRS using OK 2 a computer R6 1a The user shall be able to delete a contact item from the MRS OK T5c using a mobile phone R6 1b The user shall be able to delete a
12. 1 2 Admin Guide http download forge objectweb org sync4j sync4j syncconnectorexchange admin gui de 2 2 pdf Wireless Application Protocol Forum Ltd Wireless Markup Language WML Document Type Definition version 1 1 1998 1999 http www wapforum org DTD wml 1 1 dtd J A Audestad Kompendium TTM 4125 Distribuert prosessering og mobilitet Trondheim Tapir Akademisk Forlag Kompendieforlaget 2004 60 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Appendix A Implementation A 1 Servlet The servlet PDIServlet was included in the Sync4j bundle and is extended with search functionality and possibility to save a vCard iCalendar representation of the files A number of variables relating to the information stored in the database has also been added e g home and work address birthday job title department role etc the original files are included on the enclosed CD in the folder src pimweb old JavaDoc is also generated located in srcvpimwebNavadoc Methods edited by the author processRequest e getContact updateContact Methods added by the author viewSearchResults cleanTelNumber sortCalendars compare In nested class CalendarComparator getDisplayDateFromUTC getUTCDate Search functionality The search function is implemented in such a way that the user can enter several words in a text field
13. 57 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Extension of the SyncServer to support server alert Not all devices support server alert push messages anyway so an alternative solution for notifying these devices would be useful e g a messaging system Modify Exchange SyncSource to support the synchronization of public folders Add support for more data types in MRS such as notes and tasks and also documents and files in general Implement CGI scripting filtering in Sync4j 58 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad 8 Conclusion A system consisting of a synchronization server Sync4j SyncServer and an Exchange server for storing personal data has been set up The synchronization server also functions as the central repository for company related data In addition functionality for adding modifying deleting and searching for items in this repository has been implemented for computers PDAs and mobile phones This system is net centric and facilitates location independent access and synchronization and therefore the major goal behind this thesis has been fulfilled A problem regarding the solution is the fact that it is not possible to synchronize with a subset of the repository For large organizations this is not an acceptable solution and it would lead to a consi
14. A 13 Go to Event search but Search results page is displayed with all OK OK OK this time uncheck Display events listed only future events T8 iCalendar representation Click Save iCal Download box for the event s iCal OK Not OK representation web Event is downloaded OK and the user is prompted to add it to the calendar phone T9 Search for events Go to Event search and Only events that contains the entered data in OK OK OK enter information in all fields the corresponding fields are displayed Click Search T10 Modify event View the event details The event details are listed again with all the OK OK OK again and edit the text in all modified fields displayed correctly the fields Click Modify Go to Event search and Search results page is displayed with the OK OK OK search for the event just recently modified event on the list modified Click Search 38 MRS Mobile Repository System data synchronization and storage Master s thesis by Bent Erik Skogstad Click on the event The event details page is displayed with the OK OK OK modified information T11 Delete event Click delete Confirmation dialog box will appear web OK OK OK Back to menu screen on mobile phone Confirm dialog box web Menu screen is displayed OK OK N A Go to Contact search and Search results page is displayed with the OK OK OK search for the contact just rec
15. Due to a system tray bug when changing the port from the default value 8080 this must be done from the command shell C Program Files Sync4j tools bin stopall cmd C Program Files Sync4j tools bin startall cmd Note The system tray icon will remain red after it has started Verify that the server has been properly started by accessing http localhost sync4j User interfaces 13 14 Replace folders c Program FilesNsync4jNcoolsNtomcat webapps pimweb and c Program FilesNsync4jNtoolsNtomcat Nwebapps wap With the contents of the folders pimweb and wap respectively located on the enclosed CD Repeat step 12 SyncAdmin 15 16 17 18 19 20 21 22 In the login window change the port number to port 80 Add Exchange SyncSources see Figure C 1 Figure C 2 and corresponding note Optional Change log level to ALL Recommended Change password for the Admin account Add device s for PDA s The device ID can be found when starting the SyncClient PIM Pocket PC Appendix B 1 Add user employee with password employee and principal lt employee sc pim ppc gt The username employee must also exist in the Exchange server Add device for mobile phone s The device ID is the mobile phone s IMEI number This can usually be found by pressing 06 on the mobile phone and only the first 15 digits should be entered Add principal employee IMEI number 75 MRS Mobile Repository System
16. Event search Add event Figure A 5 Front menu A 3 1 Contacts The following screenshots are included Figure A 5 Front menu Figure Search for contact Figure A 7 Add contact e Figure A 8 Contact search results Figure A 9 Contact details 66 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Mobile Repository System Mozilla Firefox Edit View Bookmarks Tools Help E CO httpsy129 241 219 132 pimweb main jsp2main maingdb contact amp idemo contact amp task search Search for contact Name Company Job title Department Role Telephone number Address Figure A 6 Search for contact Mobile Repository System Mozilla Firefox File Go Bookmarks Tools Help c 0 9 httpjt29 241 219 132 pimwebjmain jsp main main amp dbcontact amp demo contact amp task add Add contact General Title Firstname Middle name Lastname Sufix i Nickname 1 Personal Street Postal Code City State Country Birthday yyyy mm dd Home Phone Home Fax m Figure A 7 Add contact 267 MRS Mobile Repository System Net centric data synchron
17. Last When the device in question stores the Next anchor it is able to compare whether the sync anchor is the same as the lt Last gt anchor sent by another device If Next and Last do not match the last session did not terminate correctly and slow synchronization is initiated Otherwise fast synchronization can be used It is vital that the stored synchronization anchors are not updated before the synchronization session 15 finished The example in Figure 3 2 1s an initialization message from the client to the server since the lt Source gt lt LocURI gt is a mobile phone IMEI number line 8 and the lt Target gt lt LocURI gt is the IP address of the server line 7 This message and the following examples are copied from the server log file of the implementation 1 lt SyncML gt 2 SyncHdr 3 lt VerDTD gt 1 1 lt VerDTD gt 4 lt VerProto gt SyncML 1 1 lt VerProto gt 5 SessionID 7 SessionID 6 lt MsgID gt 1 lt MsgID gt Target LocURI http 129 241 219 132 sync4j sync LocURI Target 8 lt Source gt lt LocURI gt 354007004732258 lt LocURI gt lt Source gt 9 lt Cred gt 10 lt Meta gt lt Format gt b64 lt Format gt lt Type gt syncml auth basic lt Type gt lt Meta gt 11 lt Data gt ZW1wbG95ZWU6ZW1wbG95ZWU lt Data gt 12 lt Cred gt 13 lt Meta gt lt MaxMsgSize gt 2700 lt MaxMsgSize gt lt Meta gt ETP MRS Mobile Repository System Net centri
18. Repository System data synchronization and storage Master s thesis by Bent Erik Skogstad Mobile Repository System Mozilla Firefox Go Bookmarks Tools Help ML d A L http 129 241 219 132 pimweb main jsp main main 3Ftask 3Dview 26demo 3Dcalendar 26item 3D1 115730846226 26db Go RESOURCE Event details Subject Meeting Starting date ddimmiyyyy 5 2005 Starting time hh mm Ending date ddimmiyyy 05 08 2005 Ending time hh mm ho 0 Eventtype j Location London Description Staff meeting Update Delete Save ICal These fields are mandatory Done Figure A 13 Event details MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Appendix User Manual the installation steps listed in Appendix B must be completed before the devices can access the SyncServer At the time of writing the system is up and running using the IP address specified in the following steps B 1 PDA The following steps are applicable for PDAs with Windows Mobile operating system 1 Download and install SyncClient PIM Pocket PC Windows Mobile 1 6 6 on the PDA The installation file is available on http sync4j funambol com main jsp main zdownload stable The file is also avail
19. cheaper and faster network connection using the pass through mode and out of office the user can still connect to the synchronization server The remote synchronization mode will be the focus of this report 2 6 Topologies There are various synchronization topologies that logically define different ways of synchronizing data The main topologies are 2 One to one Many to one Many to many Cluster and hierarchy These topologies are illustrated in Figure 2 1 2 6 1 One to one In this topology there are only one server and one client and for this reason this scheme 15 also called dedicated pair If the data is changed only on the client side there will be no conflicts using this topology When data is changed on both the server and client sides possible conflicts can for instance be identified by the server and resolved MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad 2 6 2 Many to one The many to one topology involves a central server and the data is exchanged directly between this server and a set of clients Two clients cannot exchange data directly and conflicts can therefore only occur at the central server which then resolves them accordingly 2 6 3 Many to many In the many to one topology the central server might be a system bottleneck In the many to many topology there is no central server in the sense that every client
20. first name is default so that the contacts are saved as last name first name on the phone default first name last name This way you would 40 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad enter a new contact as Olsen Hans Erik and then the correct first and last names are stored in Exchange as well A final note is that only the contact s home address as entered in Outlook Web Access is displayed on the phone 5 5 4 Summary of test results Table 5 7 summarizes the test results The requirements worked out in chapter 4 2 are divided into contacts and events and the table shows whether the requirement is fulfilled for the different devices Finally the corresponding test scenario according to the previous chapters 15 given Table 5 7 Summary of test results R1 The system shall use an open source implementation of a server R2 The system shall use SyncML DS over GPRS and or WLAN R3 1a The user shall be able to synchronize the contact list on a OK T13b T16b mobile phone with the server R3 1b The user shall be able to synchronize the calendar on a mobile OK T17b T20b phone with the server R3 2a The user shall be able to synchronize the contact list on a PDA OK T13a T16a with the server R3 2b The user shall be able to synchronize the calendar on a PDA OK T17b T20b
21. heri rr 27 23 23 Fil system database uoce ieri ER 27 53 WEB USER FUNCTIONALITY dEE 28 3S SCAFCH Jor CONTACIS ias o aln e ttp tod S reb PEDE RE Ie liad 29 3 3 2 30 5 3 3 17 UITIUM 30 2 4 TOR E 31 SESS Add New Mere 32 5 3 6 EHE COLA Se 32 54 WAP USER FUNCTIONALITY 32 5 4 1 TORTOR 33 5 4 2 34 5 5 TS TING sissies UR 36 3 3 1 T E T I 36 iIDserfunctionalilys ar ote d me e ot vm A 37 5 5 3 Synchronization with Exchange server 39 5 54 Summary Of test results ses eco tete tne bata exe SERE EV PER Vola Eb uva nivel ea Deko a re ua 41 6 BUSINESS CONSIDERATIONS een oaa eoe ae eterna ino SEEE 43 6 1 RODES 43 6 2 BUSINESS RELATIONSHIPS e Ere 44 6 3 SERVICE DEPLOYMENT vss erp etos oet e ue bode guess ET ye euer Eos de Cre eei ee pep 45 6 3 1 VADINA PE EEE
22. item from the MRS using a computer R6 3b The user shall be able to delete a calendar item from the MRS using a computer R7 1a The user shall be able to search for a contact item in the MRS using a mobile phone R7 1b The user shall be able to search for a calendar item in the MRS using a mobile phone R7 2a The user shall be able to search for a contact item in the MRS using a PDA R7 2b The user shall be able to search for a calendar item in the MRS using a PDA R7 3a The user shall be able to search for a contact item in the MRS using a computer R7 3b The user shall be able to search for a calendar item in the MRS using a computer R8 1a The user shall be able to save a contact item in MRS locally on his her mobile phone R8 1b The user shall be able to save a calendar item in MRS locally on his her mobile phone R8 2a The user shall be able to save a contact item in MRS locally on his her PDA R8 2b The user shall be able to save a calendar item in MRS locally on his her PDA R8 3a The user shall be able to save a contact item in MRS locally on his her computer R8 3b The user shall be able to save a calendar item in MRS locally on his her computer H9 It shall be possible to display only available people i e persons who do not currently have appointments in their calendar related to requirements R7 xa R10 The central database must give the possibility to register a contact s role title and group department membership with a contact R11 It sh
23. list of contacts is saved locally on their devices Betty in the reception adds the new phone numbers in the central employee database Afterwards the database is synchronized with the devices of all employees in Top Consulting so that they can reach Michael and Sarah Table 4 3 Use case 3 New contact information Use case description A new contact is added to the central list of contacts and all the contact lists on the users devices are synchronized with the server Actor Person in charge of personnel Flow 1 The user logs on the central server 2 The user chooses to add a new contact 3 The user enters all available information and group department memberships 4 The server sends a Server Alert to the users either to the entire system or to a relevant group department 5 The users synchronize their devices with the server Requirements e It shall be possible to add a new contact to the central database e The system shall be able to issue server alerts when items change requesting users to initiate synchronization 4 1 4 Calendar appointment John is to set up a meeting with two other co workers Susan and Tom He uses a laptop to log on to the synchronization server through the web interface The system has information about the employees calendars and this facilitates that John is not allowed to add a new appointment that is in conflict with other Susan s and Tom s other appointment
24. omitted since they are reasonably self explanatory Table 5 1 Contact fields for add contact interface General Personal Business e Salutation e Street Company e First name e Postal code e Department e Middle name e City e Job e Last name e State e Role e Suffix e Country e Street e Nickname e Birthday e Postal code e e Home phone e City e Home fax e State e Mobile phone e Country e Business phone e E mail 5 3 3 Contact details When the user has initiated a search and the results are shown on the screen he she can click on the desired contact and view the contact s details In this view the user can modify the 30 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad information stored for this contact and also delete the entire contact listing A vCard representation of the contact can also be downloaded Figure A 9 shows a partial view of the details of a sample contact 5 3 4 Search for events The users can also search for events He she can enter search criteria in the following fields Subject e Starting date after e Starting date before e Event type Location Description e Display only future events checked is standard If no information is entered the search will list all future events in the database Subject A match occurs when all the words entered are a substring of the event s subj
25. presented 1 1 Background and motivation With a growing amount of mobile devices for both private and professional use there is a greater need to manage contact data calendar information notes tasks etc This information needs to be consistent in the sense that a user should have access to the same correct data independently of which device he she is currently using Synchronization provides a means to achieve this consistency Traditionally synchronization has taken place between for instance a computer and the different mobile devices directly but this operation is location dependent since the user has to be physically near the computer to be able to synchronize A location independent solution would therefore be of much greater value and this is one of the main drives behind this thesis The idea is that mobile devices can access a centralized server that stores the necessary information and in that way be able to synchronize their content remotely It is not always practical that the user synchronizes his her device with the entire content of the server Nevertheless the user still should have the possibility to get important information from the server and also update the central data Therefore it is desirable that there exists user interfaces and functionality for retrieving this information In addition to data synchronization this is also an important drive behind the thesis 1 2 Scope and limitations The data type consi
26. server keeps list of mappings between the identifiers used by the server and the identifiers used by the client s Synchronization usually involves the client sending a list of the records that have changed since the last synchronization The server also generates a list of records that have changed in the same time period and then compares the two lists Every record that exists in both lists is identified as a conflict and resolved according to certain preferences described next 1 presents a synchronization matrix for two databases database A and database B see Table 2 3 This table illustrates the actions to be performed whenever an item changes in one or both of the databases Table 2 3 Synchronization matrix from 1 The table illustrates in which situations conflicts arise as well as actions to be performed in case of changes that does not lead to conflicts Grey cells means that the items are either equal or that no action is necessary Conflict Conflict Conflict Conflict B replaces A Conflict Conflict Delete target Conflict Conflict Conflict B replaces A B replaces A Conflict Delete target A replaces B B replaces A A replaces B A replaces B A replaces B 2 3 3 Conflict resolution As can be seen from Table 2 3 several change combinations can lead to conflicts There are many ways to resolve these conflicts Manual conflict resolution means that entries are simply duplic
27. the same machine as the Sync4j server but this database could might as well be located at a remote location The Exchange server 15 located in the same intranet as Sync4j server and is also accessible from outside this network As with the database the Exchange server could also be located at a remote location 25 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Company data Persona data 2 Exchange server Figure 5 1 System overview Mobile phones and PDAs connect to the Sync4j server over a GPRS and WLAN connection respectively The Sync4j server has a database with central company data and is also connected to an Exchange server that stores the users personal data The solution presented in this report will be based on storing central company information using the Sync4j server s file system database The users will also have an Exchange account that can be used to store personal contacts calendar events etc The data stored in Exchange is also the data that is synchronized with the users mobile devices Users can search for central company data using a web interface for PDAs and computers and a WAP interface for mobile phones Note that the Exchange server is used in this implementation for storing personal data but the personal data can be stored in any other database on the synchronization server or on a remote server Hence
28. third party contributes to operations and maintenance The roles of billing and customer care are meant to be associated with the customer that buys the service so these roles are located at the retailer since the retailer is the customer s point of contact Consulting could also be an overlapping role between the retailer and the third party service provider but this possibility is not illustrated in the figure Case illustration A medium sized company wants to install MRS It does not have the capacity to run the synchronization server itself and therefore wants to outsource it This company has specific needs and Telenor Business Solutions as the retailer is contacted to help developing a solution that will make sure the company s requirements are fulfilled In this case Telenor will be the synchronization provider and possibly also the datastore provider Telenor can also 48 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad function as the company s connectivity provider both as an ISP and as a mobile phone operator offering GPRS access Telenor Mobil Telenor could require a monthly subscription fee for offering this service to the company In addition revenue is generated by offering connectivity Finally Telenor could offer e g upgrades and operations maintenance either at a fixed price or as a part of the subscription The actor role mappings a
29. x vcard lt Type gt lt Meta gt lt Item gt lt Source gt lt LocURI gt cbb0135ac6c3894b8816f93031c606c20000000130ac lt LocURI gt lt Source gt lt Data gt e N BEGIN VCARD VERSION 2 1 N Skogstad Bent Erik 0 FN Skogstad Bent Erik TEL CELL 4712345678 END VCARD lt Data gt lt Item gt lt Add gt 2 O Sync Figure 3 3 Add command from log file 13 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Let us say that this item is being modified Instead of the aaa tag there would be a Replace tag in sync section see Figure 3 4 lines 5 23 The example shows that the vCard has been modified on the server since the target database is on the client line 3 and the source database is on the server line 4 Sync lt CmdID gt 3 lt CmdID gt 1 2 E Target LocURI EriPBDB LocURI Target 4 lt Source gt lt LocURI gt exchange contacts lt LocURI gt lt Source gt 5 lt Replace gt lt CmdID gt 2 lt CmdID gt lt Meta gt lt Type gt text x vcard lt Type gt lt Meta gt lt Item gt lt Target gt lt LocURI gt 0000000003A3 lt LocURI gt lt Target gt lt Data gt BEGIN VCARD VERSION 2 1 N Skogstad Bent Erik Student FN Skogstad Bent Erik ADR HOME Weidemanns vei 17 Trondheim 7014 Nor
30. 2 Input fields for WAP contact interfaces Search for contacts e Name e Company e Department e Job title e Role e Telephone number e Address Contact details Add contact e First name e Last name e Company Department e Job title e Role e Work address street postal code city state country e Home address street postal code city state country e Mobile phone e Business phone Home phone Home fax E mail 5 4 2 Events The WAP event interfaces are displayed in Figure 5 5 34 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad MHS MRS Figure 5 5 Screen photos of event interfaces 1 Search for events 2 Search results 3 Event details top of page 4 Event details bottom of page 5 Add event 95 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Table 5 3 lists the attributes input text fields for the various event interfaces The processing and content of these fields are identical to the web interface For the description of these fields see chapters 5 3 4 5 3 6 Table 5 3 Input fields for WAP event interfaces Search for events e Subject e Starting date after dd mm e Starting date before dd mm e Event type e Location e Descr
31. 43 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad same as the synchronization provider either the customer or a third party The synchronization provider and datastore provider could also be two separate parties with the synchronization provider buying storage from an external datastore provider Retailer The retailer is the role that sells the actual service to the customer The retailer role can be decomposed in several different roles as depicted in Figure 6 1 Retailer e amp mL e vstem integration Figure 6 1 Role decomposition of the retailer modified from 14 The retailer should provide consulting services to assess the company s needs and to come up with the appropriate solution The roles indicate that the retailer can be hosting the synchronization server and store the customer s data No matter which instance is hosting the service the retailer will have a key role in the deployment or installation of the service System integration might be needed for integrating the service with the customer s current system and or if the complexity of the synchronization and datastore scheme requires special integration efforts Operations and maintenance is needed to make sure that the service is functioning properly at all times Customer care will try to acquire new customers and follow up the existing customers to ma
32. 7 OK OK OK Fill in the desired The contact details just entered are displayed OK OK OK information use all fields Click Add Go to Contact search and Search results page is displayed with the OK OK OK search for the contact just recently added contact on the list entered Click Search 257 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad As can be seen from Table 5 4 save vCard did not work as intended with the PDA The download dialog box was opened but the only possibility was to save it as a JSP file The file extension would have to be renamed to vcf and then opened to be added to the contact list The test scenarios for events are very similar to the contact scenarios Table 5 5 displays the test results The actions listed in the table can be seen as a consecutive series of actions These actions are grouped and the groups are each given an identifier Tx Table 5 5 Event test scenarios Click on link Event search Search page is displayed Figure A 10 OK OK OK T7 List events Click Search Make sure Search results page is displayed with only OK OK OK the Display only future future events listed Figure A 11 events is checked Click on an event listed in The event details page for this event is OK OK OK search results displayed with the correct information in all fields Figure
33. DIX C INSTALLATION 8 5 5 74 APPENDIX D ENCLOSED HM 78 MRS Mobile Repository System data synchronization and storage Master s thesis by Bent Erik Skogstad List of figures FIGURE 2 1 SYNCHRONIZATION TOPOLOGIES 5 45 AR TRE ee abere FREE Ee ERR FR Es 9 BIGURES 1 SYNCML FRAMEWORK re Eee a erras 11 FIGURE 3 2 INITIALIZATION SYNCML MESSAGE ssccccssssececsesceceesseeecssseeceesceecsesaececseseecsesaeeecseneeeecsneeeesesnreeeseas 13 FIGURE 3 37 ADD COMMAND esses iicet ref E ence es OR FERENT FINEM S FER D cadence 13 FIGURE S4 REPLACE COMMAND ar Tel He 14 FIGURE 3 5 DELETE COMMAND UR TEFIREN ENTE ERE 14 FIGURE 3 6 SYNC4J SYNCSERVER LAYERED 4 412 002220 40400 00110000100000000000 8 16 BIGUBRES 7 EXECUTION BLOW UE RD FERREA D 17 FIGURE 3 6 EXAMPLE VCARD 5 ond tees ei ep de Parure pred acces 19 FIGURE 3 9 EXAMPLE ICALENDAR
34. LE EXE EN 62 FIGURE 2 MAIN JSP FOR WEB INTERFACE e cases ae ce Y doa ma 63 FIGURE A 3 PROCESSREQUEST egere er eed Oye oed ev esie doute ue deoa rad OR 64 FIGURE A 4 WML CARD INCLUDED IN SEARCH JSP CONTACT SEARCH cesses eee enne nennen enne nns 65 FIGURE FRONT D m 66 FIGURE A16 SEARCH FOR CONTACT deste usta 67 FIGURE A7 ADD CONTACT ide Dette eerie tct ar see vto ducta eva 67 FIGURE 8 CONTACT SEARCH RESULTS irte Rer actos Dec euo T Pu Rueda 68 FIGURE A 9 CONTAGCTDETXILS 2 reete 68 FIGURE SEARCH FOR EVENT i orte p deed bx eee axis ere e ees 69 FIGURE A 11 EVENT SEARCH RESULTS e Pe Eyre bie Eee boe sale rere e ess 70 FIGURE A12 ADD EVENT eris over 70 FIGURE A 13 EVENT DETAIES 5 5 5 rrr terrere Eee sprees 71 FIGURE C 1 EXCHANGE CONTACT 5
35. NORWEGIAN UNIVERSITY OF SCIENCE AND TECHNOLOGY FACULTY OF INFORMATION TECHNOLOGY MATHEMATICS AND ELECTRICAL ENGINEERING MASTER S THESIS Student s name Bent Erik Skogstad Area Telematics Title Norwegian MRS Mobile Repository System Nettsentrisk synkronisering og lagring av data Title English MRS Mobile Repository System Net centric data synchronization and storage Description There are numerous mobile devices that handle address data notes calendar information etc Synchronization of such data between different devices is on the other hand quite cumbersome A mobile phone and a PDA synchronize their data with a computer which assumes a location dependent operation The assignment is to design and implement a net centric system for storing information to be downloaded to a mobile phone and a PDA The devices must be able to update the system also through a web based interface The system is to be implemented using standard protocols from OMA and an open source implementation of a server for instance Sync4j MRS shall communicate with mobile terminals using SyncML DS over GPRS or WLAN From mobile terminals the user shall be able to request search for information in MRS for instance a company s employer address list documents etc Client user interface and server for this system are to be implemented MRS will be realized in the PATS lab and piloted for the employers at Telenor R amp D If possible it is wanted tha
36. Title gt lt FileAs gt Brown Vincent lt FileAs gt lt MiddleName gt lt MiddleName gt lt Suffix gt lt Suffix gt lt LastName gt Brown lt LastName gt lt Revision gt 20050407T150934 lt Revision gt lt contact gt Figure 5 2 XML representation of a contact The contact Vincent Brown is stored as a single XML formatted file in a contacts folder The content of the figure is taken from an example contact file in the Sync4j installation 5 3 Web user functionality The system shall offer the possibility to search among the data stored in the central database The user must be able to perform the search from a set of devices a computer a PDA and a mobile phone User interfaces for these different devices have been implemented The user interfaces are implemented only for the file system database i e not for the Exchange system To search for data stored on the Exchange server the user can search for contacts and other information using for instance Outlook Web Access In the Sync4j bundle there is a web demo included that lists contacts and calendar information and also gives the possibility to add delete and modify this information The web interface is developed using JSP pages and a Java servlet and these are extended to include searching functionality and the option to save vCards and iCalendar representation of the items Since the original demo only includes a limited set of contact information fields many fie
37. able on the enclosed CD install syncclient pim ppc 1 6 6 exe 2 Run program and choose Edit gt Communication Settings SyncServer URL http 129 24 1 219 132 sync4j sync Username employee Password employee 3 Choose Edit Synchronization Settings Check Contacts and or Calendar 4 Choose Remote Settings Contacts Jexchange contacts pda Calendar Jexchange calendar pda For synchronizing with the file system database central repository instead of with the Exchange server use instead sifcontact and sifcalendar respectively B 2 Mobile phone For accessing central repository add bookmark with the address http 129 241 219 132 wap index wml 72 MRS Mobile Repository System data synchronization and storage Master s thesis by Bent Erik Skogstad The following synchronization configuration steps are applicable for Sony Ericsson k700i with Norwegian software 1 optional Go to Telefonliste menu item row 3 column 2 choose Valg gt Avansert gt Synkr rekkefglge Check etternavn 2 Goto Kommunikasjon menu item row 4 column 1 choose Synkronisering gt Ny konto 3 Navn lt anything gt Serveradresse http 129 241 219 132 sync4j sync Brukernavn for server employee Serverpassord employee Tilkobling any valid WAP connection 4 Choose Programmer Check Telefonliste and Avtaler 5 Choose Progr
38. aintenance relating to the service so this is considered to be an overlapping role 46 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Case illustration St Olav s Hospital in Trondheim is going to install MRS Due to its size it 15 natural that the hospital itself hosts the synchronization server and stores the data Thus the hospital has the role as the customer as well as the synchronization provider and datastore provider Telenor Business Solutions as the retailer could assist the hospital with the deployment of MRS and integrating it with the hospital s current system Telenor can also function as the hospital s connectivity provider both as an ISP and as a mobile phone operator offering GPRS access Telenor Mobil Hence revenue is generated by offering connectivity and also a compensation for the deployment of MRS In addition Telenor could offer e g upgrades and operations maintenance either at a fixed price or as a subscription The actor role mappings are listed below The role decompositions shown in Figure 6 4 still apply End user Employer nurses doctors administrative personnel etc Customer St Olav s Hospital Connectivity provider Telenor Telenor Mobil Synchronization provider St Olav s Hospital Datastore provider St Olav s Hospital Retailer Telenor Business Solutions 6 3 2 Internal service In this scenario the cu
39. all be possible to schedule group events i e choose one or more other users to include in the appointment R12 The system shall be able to issue server alerts when items change requesting users to initiate synchronization 24 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad 5 System description This chapter presents the system used in the assignment First an overview of the system is given The synchronization server is described in further detail in the subsequent chapter How to facilitate the synchronization between mobile devices and the server is also explained The implementation focus is directed towards user functionality Hence this constitutes the major part of this chapter Both web browser interfaces designed for computers and interfaces for mobile phones WAP are described in detail as well as the underlying functionality Finally results from the testing of this functionality as well as the synchronization testing are given 5 1 System overview Figure 5 1 shows a high level view of the system It consists of a synchronization server Sync4j server a Microsoft Exchange server and mobile devices such as mobile phones and PDAs Through the Sync4j server the users will synchronize their contact and calendar information on their mobile devices with the data stored in the Exchange server In this implementation the database resides on
40. also acts as a server clients must be able to get updates and send updates to every other client This is the most complex topology since all the clients must be able to detect and resolve conflicts On the other hand this topology is the most robust since you eliminate the bottleneck that exists in the many to one topology 2 6 4 Cluster and hierarchy The cluster and hierarchy topologies can be seen as hybrids of the many to one and many to many topologies as described in the two previous chapters In a cluster topology there are a cluster of servers which all contain copies of the data and replicate between each other Only one of the servers in the cluster keeps the authoritative copy The servers may be geographically distributed to reduce the distance between server and clients In a hierarchy topology the servers are organized in a hierarchical manner with the servers at one level at the same time acting as clients of a server on the level above In both topologies the overall system will not be affected by a failure in one of the servers MRS Mobile Repository System data synchronization and storage Master s thesis by Bent Erik Skogstad 1 2 3 4 5 Figure 2 1 Synchronization topologies from 2 1 One to one 2 Many to one 3 Many to many 4 Cluster 5 Hierarchy Circles represent clients and squares represent servers MRS Mobile Repository System data
41. aminnstilling gt Telefonliste Databasenavn Jexchange contacts Brukernavn not applicable Passord not applicable For synchronizing with the file system database central repository instead of with the Exchange server use instead contact 6 Choose Programinnstilling gt Avtaler Databasenavn exchange calendar Brukernavn lt not applicable gt Passord lt not applicable gt For synchronizing with the file system database central repository instead of with the Exchange server use instead calendar MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Appendix C Installation Steps In this appendix the steps to install configure and administrate the Sync4j SyncServer are listed C Program Files Sync4j refers to the installation directory of the current implementation and must be changed accordingly In the same manner IP address 129 241 219 132 is the address of the server and must also be changed Install SyncServer 1 Download and install Sync4j bundle 2 2 for Windows available from http sync4j funambol com main jsp main download_stable The file is also available on the enclosed CD install sync4j 2 2b4 exe Reconfigure the server to use port 80 2 Inc Program Files Sync4j tools tomcat conf server xml change connector port to 80 lt Define non SSL Coyote HTTP 1 1 Connector on port 8080
42. ata on the users devices A user is most likely to have both personal contacts and business contacts When synchronizing the personal contacts must not be added to the central company datastore So unless the users have separate devices for work and private use or the devices themselves are able to distinguish between personal and business data this problem would persist if all data is synchronized with a common datastore This is the reason why the users only synchronize with their private Exchange contacts calendar folder in the solution presented in this report These folders could contain a mix of personal and business contacts events The data in MRS are accessible through web interfaces and the user can save items in MRS to his her device and synchronize with the Exchange server This scheme most likely leads to consistency problems If an item is changed in MRS then the users that have previously saved a copy of this item is not aware of the change The original idea was to create public Exchange folders containing contacts calendar information etc but SyncConnector Exchange can only synchronize the users private folders A workaround to this problem could be to create a generic common user for synchronization purposes alternatively a user for each department group that would synchronize the same data Still this would not have solved the problem with separating business and personal data 52 MRS Mobile Repository Syst
43. ated and marked as conflicts leaving the resolution to the user Automatic conflict resolution is on the other hand done by the server based on user preferences meaning that one of the conflicting records is chosen as winner and the other one is deleted The preferences can for instance be Client side updates always win e Server side updates always win MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad e Latest change wins A third type of conflict resolution is merging the conflicting records into a new one For this to work the server needs to analyze the structure of the record and be able to identify which fields that have changed 2 4 Slow versus fast synchronization Fast synchronization involves synchronizing only the items that have changed since the last synchronization 1 The precondition of this synchronization mode is that the last synchronization was completed successfully If this condition is not fulfilled for example due to a device reset slow synchronization is necessary In this mode the client has to send its entire database to the server The server then compares it with its own database and sends the modifications back to the client When two devices are synchronizing for the first time slow synchronization must be used 2 5 Usage modes This section presents the three physical modes in which synchronization is typically performed ac
44. between the GUIDs on the server and the LUIDs on the client devices see Table 2 1 1 101 1 201 102 2 202 103 3 203 Table 2 1 LUID GUID mapping based on 2 The GUID entries are the server s identifiers and a mapping between these GUIDs and each device s LUIDs is necessary It is also possible that the server and devices generate GUIDs that must be used by all other devices This eliminates the need of a mapping table since all of the client LUIDs for an item will be equal An ID scheme that defines a convention on how to generate identifiers may also be agreed upon by the clients and the server Other approaches may also be considered 2 2 Change detection Change detection involves identifying what data that have changed since the last synchronization 1 Additional information associated with each record such as timestamps and state information can be used for this purpose Timestamps indicate the point in time of MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad the last synchronization and the state information could indicate if the record is new updated or deleted Table 2 2 illustrates a possible table in a database used for change detection 1 N 2005 05 01 18 24 2 0 2005 05 02 08 30 D 2005 05 02 08 35 Table 2 2 Example database change table modified from 1 The table
45. c data synchronization and storage Master s thesis by Bent Erik Skogstad 4 lt SyncHdr gt 5 SyncBody 6 Alert 7 lt CmdID gt 1 lt CmdID gt 8 lt Data gt 200 lt Data gt 9 lt Item gt 20 lt Target gt lt LocURI gt exchange contacts lt LocURI gt lt Target gt 21 lt Source gt lt LocURI gt EriPBDB lt LocURI gt lt Source gt 22 lt Meta gt lt Anchor gt lt Last gt 2152 lt Last gt lt Next gt 2154 lt Next gt lt Anchor gt lt Meta gt 23 lt Item gt 24 lt Alert gt 25 lt Final gt lt Final gt 26 lt SyncBody gt 27 lt SyncML gt Figure 3 2 Initialization SyncML message from log file The next figure Figure 3 3 shows how an actual synchronization command is represented The root of the synchronization is the lt Sync gt tag This tag has lt SyncBody gt as its parent element and contains the command ID target and source information and which synchronization operations that will be executed The most common are add replace and delete In this example the lt Add gt command lines 5 to 19 specifies that a new item is to be added and a vCard representation of an item is given in pata tag lines 10 to 17 1 Sync 2 CmdID 3 CmdID 3 Target LocURI EriPBDB LocURI Target 4 lt Source gt lt LocURI gt exchange contacts lt LocURI gt lt Source gt lt Add gt lt CmdID gt 2 lt CmdID gt lt Meta gt lt Type gt text
46. calendar item from the MRS OK TITE using a mobile phone R6 2a The user shall be able to delete a contact item from the MRS OK T5b using a PDA R6 2b The user shall be able to delete a calendar item from the MRS OK 7116 using PDA R6 3a The user shall be able to delete a contact item from the MRS OK T5a using a computer R6 3b The user shall be able to delete a calendar item from the MRS OK T11a using a computer R7 1a The user shall be able to search for a contact item in the MRS OK T1c T3c using a mobile phone R7 1b The user shall be able to search for a calendar item in the MRS OK T7c T9c using a mobile phone R7 2a The user shall be able to search for a contact item in the MRS OK T1b T3b using a PDA R7 2b The user shall be able to search for a calendar item in the MRS OK T7b T9b using a PDA R7 3a The user shall be able to search for a contact item in the MRS OK using a computer R7 3b The user shall be able to search for a calendar item in the MRS OK 7 using a computer R8 1a The user shall be able to save a contact item in MRS locally on OK T2c his her mobile phone R8 1b The user shall be able to save a calendar item in MRS locally OK T8c on his her mobile phone 8 2 The user shall be able to save a contact item in MRS locally on Not as T2b his her PDA intended R8 2b The user shall be able to save a calendar item in MRS locally Not as T8b on his her PDA intended R8 3a The us
47. contains the last update of each item and the state indicates whether the item is new N updated U or deleted D If these types of additional information are not available more complicated approaches must be used such as comparing the contents of an item field by field 2 3 Conflicts One of the main challenges with data synchronization is the arising of conflicts Due to the fact that the same data resides on multiple devices it is likely that the same entry may be changed on more than one device Aspects related to conflicts are presented here according to 2 2 3 1 Conflicting updates A write write conflict occurs when the same field is updated concurrently in two different copies of the datastore A read write conflict is due to a stale read a situation where one receives an entry from one copy of the datastore that is not up to date A third type of conflict is constraint violation To illustrate a constraint that only allows numbers between 0 and 100 is changed so that now only numbers between and 50 are allowed In another copy of the datastore a user enters a value between 50 and 100 which still is in accordance with the old constraint rule but in clear violation to the updated rule MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad 2 3 2 Conflict detection records are uniquely identified by an identifier and the central
48. cording to 2 These modes are local pass through and remote 2 5 1 Local The local mode typically involves a computer and a mobile device that is connected to this computer via a serial infrared USB or Bluetooth connection The server is an application running on the computer and the data can be retrieved from applications such as Lotus Notes and Microsoft Outlook 2 5 2 Pass through This mode is similar to the local mode since it also means that a mobile device is connected to a computer But instead of the computer functioning as the synchronization server the device s request is passed forward to the real synchronization server It is often beneficial to have the data to be synchronized stored at a remote location instead of locally and this mode facilitates such a scheme On the other hand the user must synchronize with a remote server MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad even though he she is not on the road generating some additional network traffic compared to the local synchronization mode 2 5 3 Remote In the remote synchronization mode there is no pass through synchronization server in the middle The mobile device establishes a network connection directly with the real synchronization server Remote synchronization and pass through synchronization can successfully be used in combination At the office the user can benefit from a
49. derable amount of data to be transferred when synchronizing especially the first time It would also be cumbersome to handle this amount of data on e g a mobile phone Filtering is a possible solution to this problem but it is currently not implemented in Sync4j The SyncServer is fully accessible from outside the internal network where it is installed to offer true location independency This places strict requirements to authentication Users who synchronize their data are authenticated using basic authentication but it would be more secure to use MD5 digest access authentication This is not implemented in Sync4j central repository is accessible by anyone who knows the server address and this is of course not satisfactory in a real solution offered by a retailer The solution makes it possible to synchronize contacts and events using the SyncML protocol as well as perform operations on a central repository also consisting of contacts and events As mentioned there are a number of issues needed to be worked out in order to offer a service but this solution can be seen as a starting point for further development 59 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad References 1 2 3 4 5 6 7 8 9 10 11 12 13 14 The Sync4j Project Sync4j SyncServer Developer s Guide January 2005 ht
50. dered in this report is related to contacts and calendar events The thesis focuses mainly on developing functionality for mobile phones PDAs and computers More specifically the functionality is related to the addition modification and deletion of contact and event items as well as searching for data among these items User interfaces are MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad necessarily required to demonstrate the functionality but developing these interfaces is not the main area of the thesis The assignment description implies that SWOT analyses are to be worked out This has not been the focus of the work in this report Instead the author has directed more efforts towards other business aspects such as business relationships and actor role considerations 1 3 Thesis outline Chapter 2 presents the most important principles for data synchronization These include ID handling change detection conflict detection and resolution slow and fast synchronization and synchronization topologies and types Chapter 3 introduces the SyncML framework describes the Sync4j implementation of a SyncML server and explains the vCard and iCalendar format associated with contact and event details respectively Chapter 4 presents some scenarios and use cases These will be used to gather requirements for the system Chapter 5 describes the implemented sy
51. e The example WML card in Figure A 4 is included in the file search jsp lt wml gt card 19 title Telenor MRS gt lt p align center gt SEARCH FOR CONTACTS lt br gt lt br gt lt p gt lt p gt lt b gt lt fmt message key msg fullname gt lt b gt lt br gt lt input type text name query_fullname value gt lt br gt lt b gt lt fmt message key msg org gt lt b gt lt br gt lt input type text name query_org value gt lt br gt lt b gt lt fmt message key msg dep gt lt b gt lt br gt lt input type text name query_dep value gt lt br gt 64 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad b fmt message key msg title gt lt b gt lt br gt lt input type text name query title value gt lt br gt lt b gt lt fmt message key msg role gt lt b gt lt br gt lt input type text name query_role value gt lt br gt lt b gt lt fmt message key msg tel gt lt b gt lt br gt lt input type text name query tel value gt lt br gt lt b gt lt fmt message key msg address gt lt b gt lt br gt lt input type text name query_fulladdress value gt lt br gt lt br gt lt anchor title Search gt Search lt go href main jsp main main amp demo contact amp task results method post gt
52. ect Starting date after The user can specify that only events after and including this date will be listed in the search results Starting date before The user can specify that only events prior to and including this date will be listed in the search results Event type A match occurs when all the words entered are a substring of the event s type Location A match occurs when all the words entered are a substring of the event s location 31 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Description A match occurs when all the words entered are a substring of the event s description Display only future events If checked the search will only yield events occurring on the current date or after the current date 5 3 5 Add new event The user also has the option to add a new event to the central company database The add event interface is shown in Figure A 12 The fields are listed below but further details about them are omitted since they are reasonably self explanatory e Subject e Starting date e Starting time Ending date e Ending time e Event type e Location e Description 5 3 6 Event details When the user has initiated a search and the results are shown on the screen he she can click on the desired event and view the event details In this view the user can modify the information stored for this event and also dele
53. em Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad It would be useful if the user could synchronize with a subset of the data stored in MRS e g according to which group s and department s he she is a part of One solution could be to make a folder for each group but then you would have a consistency issue when an item belongs to more than one group Imagine a user who is a member of group modifies an item and synchronizes with the server Then the item is correct for group A but if the item is also stored in the group B folder then this item would not be updated Therefore a mapping of elements between folders is needed This solution would also waste space in storing the item in several folders On the other hand the files are very small and disk space is not the major issue Another problem with having several folders is related to authentication Basically a user of the Sync4j SyncServer has access to all the folders if he she knows the folder name Another solution could be to create a database with users and their respective group membership Each item would have to be assigned an additional data field describing which groups that will synchronize this item In this way each item would only be stored once and the consistency and waste of space problems would be eliminated But the problem relating to separation of personal and business data would still remain Another approach is to apply a
54. ends all of its data to the server and the server is expected to replace all data in the target database with the data sent by the client i e the client has the right of way Refresh synchronization from server only Similar to the above synchronization type except that it is the server that sends all of its data to the client and the client is expected to replace all data i e the server has the right of way One way synchronization from server only The client gets all modifications from the server but the client does not send any of its modifications to the server Server alerted synchronization The server alerts the client to perform synchronization 3 2 The Sync4j Project The Sync4j Project is an open source initiative to deliver a complete mobile application platform implementing the SyncML protocol 6 The server SyncServer is a Java based SyncML server that can be used with any SyncML enabled client 15 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad 3 2 1 Sync4j SyncServer This chapter describes Sync4j SyncServer of the information given is taken from 1 The SyncServer architecture is layered as illustrated by Figure 3 6 The transport layer is where the client messages reach the system Currently the HTTP protocol and binding are implemented Other transport protocols may be added The protocol layer handles the interp
55. ently deleted contact not on the list entered Click Search T12 Add event Go back to menu and click Add event page is displayed Figure 12 OK OK OK on link Add event Fill in the desired information use all fields Click Add Go to Event search and The event details just entered are displayed OK OK OK Search results page is displayed with the OK OK OK search for the event just recently added event on the list entered Click Search As can be seen from Table 5 5 save iCalendar did not work as intended with the PDA The download dialog box was opened but the only possibility was to save it as a JSP file The file extension would have to be renamed to ics and then opened to be added to the calendar 5 5 3 Synchronization with Exchange server Table 5 6 shows the different scenarios tested regarding contact and event synchronization The actions listed in the table are grouped and the groups are each given an identifier Tx Outlook Web Access was used to modify add delete items on the server Table 5 6 Synchronization test scenarios T13 Transfer of contacts from server Start out with an empty contact list on the device All the items on the server OK OK and synchronize with the contacts on the server displayed in the device s contact list T14 Modify contact Modify a contact on the device and synchronize The modified contact is also OK OK with the
56. er shall be able to save a contact item in MRS locally on OK T2a his her computer R8 3b The user shall be able to save a calendar item in MRS locally OK T8a on his her computer H9 It shall be possible to display only available people i e persons Not who do not currently have appointments in their calendar implemented related to requirements R7 xa R10 The central database must give the possibility to register a OK T6 contact s role title and group department membership with a contact R11 It shall be possible to schedule group events i e choose one or Not more other users to include in the appointment implemented R12 The system shall be able to issue server alerts when items Not change requesting users to initiate synchronization implemented Note regarding R12 Although server alerted synchronization is specified in the SyncML protocol see chapter 3 1 2 the most recent Sync4j server implementation does not offer this possibility 1 Therefore the users have to initiate synchronization themselves e g in the beginning of their work shift and possibly at regular intervals throughout the shift 42 MRS Mobile Repository System data synchronization and storage Master s thesis by Bent Erik Skogstad 6 Business considerations This chapter will look into which roles are needed if the Mobile Repository System shall be deployed in the market Business relationships between these roles will al
57. essage that user B has accepted and the status of the appointment is Active Alternative flow 8 User B is not able to attend this meeting refuses and synchronizes with the server 9 User A is notified through Server Alert that user B has refused the suggested meeting and user A can try to find a new time steps 1 5 Requirements e It shall be possible to choose which persons to include in an appointment e The participants must be alerted about the appointment through Server Alert and they also have to confirm the suggested appointment 4 2 List of requirements Requirements are gathered from the scenarios and more requirements are deduced from these These as well as requirements specified explicitly in the thesis description are concretized and listed in Table 4 5 23 MRS Mobile Repository System data synchronization and storage Master s thesis by Bent Erik Skogstad Table 4 5 List of requirements The system shall use an open source implementation of a server R2 The system shall use SyncML DS over GPRS and or WLAN R3 1a The user shall be able to synchronize the contact list on a mobile phone with the Server R3 1b The user shall be able to synchronize the calendar on a mobile phone with the server R3 2a The user shall be able to
58. filter to the datastore specifying which items to synchronize e g all contacts belonging to a certain group This would solve the problems pointed out earlier in this chapter Each item only needs to be stored in one location and this filtering should be specified so that only central company data would be synchronized excluding personal data For synchronizing personal data another datastore could be used such as e g the Exchange server Unfortunately such filtering is not currently supported in the Sync4j implementation Filtering can also be used to improve scalability and this is discussed further in the next chapter It is an easy task to set up synchronization with the data in MRS instead of the Exchange server see Appendix B but due to the problem with separating personal and business data this was not considered to be a good solution 53 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad 7 2 Scalability For large organizations it is important to be able to divide e g the contacts database into groups departments and let the users synchronize only with a subset of the entire database It is not a practical approach to have the users synchronize with the entire database if it consists of several thousand contacts The same thing goes for calendar information e g synchronize with only events that occur in the week to follow excluding all later even
59. if the term Exchange server is used in a general context in this report it can also be interpreted simply as an instance hosting the personal data 5 2 Server The server used in the implementation is Sync4j bundle 2 2 beta 4 for Windows The bundle includes the Apache Tomcat 5 0 server Administration of the server is done with SyncAdmin 1 1 3 also bundled The Sync4j server will hereafter be referred to as SyncServer 26 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad 5 2 1 SyncConnector Exchange To connect the SyncServer with the Exchange server a module is installed in the SyncServer This module is downloadable from the Sync4j web site 10 It contains a SyncConnector SyncConnector Exchange A SyncConnector is an extension to the SyncServer integrating it with an external data source 11 When the SyncServer receives a synchronization request from a client it will look for updates in its local cache 12 If some of the items have been modified it will initiate a WebDAV Web based Distributed Authoring and Versioning connection to the Exchange server The WebDAV protocol is an extension to HTTP and facilitates the development of writable web applications This makes it possible to perform operations such as create copy delete move and search for resources in the Exchange datastore In the system presented in this report the user s
60. iption e Display only future events Event details Add event e Subject e Starting date dd mm e Starting time hh mm e Ending date dd mm yyyy e Ending time hh mm e Event type e Location e Description 5 5 Testing This section summarizes the test results for both web and WAP interface as well as the results from the synchronization testing 5 5 1 Test environment The following devices software were used to verify the implementation e Mobile phone Sony Ericsson k7001 e PDA HP iPAQ Microsoft Pocket PC Version 4 20 1081 build 13100 using Internet Explorer for Pocket PC Web browser computer Mozilla Firefox version 1 0 3 36 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad 5 5 2 User functionality Table 5 4 shows the different scenarios tested regarding contacts search add modify delete save The actions listed in the table can be seen as a consecutive series of actions These actions are grouped and the groups are each given an identifier Tx Table 5 4 Contact test scenarios Click on link Contact Search page is displayed Figure A 6 OK OK search T1 List all contacts Click Search with no Search results page is displayed with all OK OK OK information entered in the contacts listed Figure A 8 tex
61. ization and storage Master s thesis by Bent Erik Skogstad Mobile Repository System Mozilla Firefox Edit View Bookmarks Tools Help 6 0 9 htpizo 241 219 132 pimweb main jsp Search results Select a contact or create a new one Brown Vincent Doe John Nordmann Kari Smith Mike Done Mobile Repository System Mozilla Firefox Edit Bookmarks Tools Help Eile View 6 0 hetpsij129 241 219 132 pimweb main jspemain main 3Ftask e3D view 26item 3D 1 1 15810895351 26db 3Dcontact Figure A 8 Contact search results RESOURCE vinuay Home Phone Home Fax Mobile Phone Business Company Department Job title Role Street Postal Code City State Country Business Phone Email Ur 12345678 23456789 34567890 Sykehuset Fadeavdelingen Jordmor Vakthavende Sykehusgeta 1 0123 Oslo Oslo Norway 45678901 Update Delete Save VCard Done Figure A 9 Contact details 68 MRS Mobile Repository System data synchronization and storage Master s thesis by Bent Erik Skogstad A 3 2 Events The following screenshots are included Figure A 10 Search for event Figure A 11 Event search results e Fig
62. ize her mobile phone with the server and shortly after she once again had her contact list intact Table 4 1 Use case 1 Transfer contact list to new phone one Use case description The user has lost her mobile phone and synchronizes the contact list on her new phone with a central server Actor Mobile phone end user Flow 1 The user logs on the central server with her new mobile phone 2 The user chooses to start synchronization of contacts 3 Since the new mobile phone does not have any contacts all the user s contacts will be copied from the central server to the mobile phone 20 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Requirements e The server shall function as a backup storage so that a user can retrieve all of his her contacts if the phone is lost or damaged 4 1 2 Contact list lookup Henry is a doctor at the Department of Neuro Surgery at St Olav s Hospital and is stuck on a lung related problem He does not know any lung specialists but his mobile phone can help him get in touch with one He performs a search in the central database after doctors related to the Department of Heart and Lung Surgery who are not busy with other appointments The search yields only one result Catherine Eckhoff He calls her and explains the problem and she is able to give him an answer over the phone After the co
63. ke sure that they are satisfied Billing subscriptions payment per use is also a key role 6 2 Business relationships Figure 6 2 shows the business relationships between the participating roles The customer buys a service from a retailer The retailer can have agreements with a third party synchronization provider and datastore provider but the retailer could also provide these 44 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad services The customer retailer synchronization provider and datastore provider all have business relationships with a connectivity provider for Internet access and the transportation of data The different connectivity providers involved must also have relationships between each other Finally the relationship between customer and end user could be for example employee employer Connectivity provider Synchronization provider Customer Retailer Datastore provider Figure 6 2 Business relationships The lines illustrate business relationships between the roles involved From the figure the synchronization provider and datastore provider are separate roles These roles might instead be covered as a part of the retailer s roles as indicated in Figure 6 1 6 3 Service deployment Three different service deployment scenarios will be described next internal network internal service and public ser
64. lds have been added to the interface Appendix A further details the servlet implementation and JSP pages In this appendix all screenshots relating to the web interfaces are gathered and the following chapters will include references to these screenshots The front menu see Figure A 5 gives the user the options to search for a contact add a new contact search for an event or add a new event 28 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad 5 3 1 Search for contacts The user can search for the following information regarding a contact see Figure A 6 Name Company Job title e Department e Role e Telephone number e Address These fields were chosen from the author s consideration of what kind of information that would be most necessary to be able to search for in an organization If no information is entered the search will list all contacts in the database Name A match occurs when all the words entered are substrings of the concatenation of the contact s salutation e g Mr Mrs Ms Dr first name middle name surname and suffix e g Jr 5565 Company A match occurs when all the words entered are substrings of the contact 5 company Job title A match occurs when all the words entered are substrings of the contact s job title Role A match occurs when all the words entered are substrings of the con
65. lid for use with mobile phones For synchronization with a PDA using the SyncClient PIM Pocket PC Windows Mobile client the conversion type needs to be set to XML and encoded must be checked The Exchange folder value must remain the same but the Name value must be changed since the MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad names must be uniquely identifiable In the current configuration two additional SyncSources have been added exchange contacts pda and exchange calendar pda MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Appendix D Enclosed CD The following directories can be found on the enclosed CD install log references report STC Sync4j SyncServer bundle 2 2 beta 4 SyncClient PIM Pocket PC Windows Mobile 1 6 6 SyncConnector Exchange 1 2 4 SyncServer log file example The references used that are electronically available This report in PDF format JSP pages and servlet code for web and WAP located in pimweb and wap respectively as well as the original files bundled with Sync4j located in pimweb old The servlet code is located in WEB INF classes PDIServlet java 78
66. nencoded vCard iCalendar format while the PDA used XML for formatting the data and the data was sent encoded This is a consequence of how the Exchange SyncSource is implemented and the data had to be formatted in this way for the respective devices 7 5 Openness The Sync4j synchronization server uses SyncML an open standard for data synchronization Any device supporting the SyncML protocol will be able to synchronize its data with the system This standard is widely adopted by mobile phones Client software for synchronizing with Microsoft Outlook also exists as well as clients for Pocket PC Windows Mobile and BlackBerry devices 10 Data from the central repository can be accessed through interfaces for mobile phones PDAs and computers using HTTP 56 MRS Mobile Repository System data synchronization and storage Master s thesis by Bent Erik Skogstad 7 6 System interface considerations If the SyncServer is to be installed in a company s internal network then it must be opened for users outside of the internal network for it to be useful A user should be able to synchronize with the server and access the Mobile Repository System at any location and at any time This on the other hand requires robust security mechanisms Currently anyone who knows the address of the SyncServer can search for information in the MRS as well as add modify and delete contacts and events Hence it is crucial that
67. nization and storage Master s thesis by Bent Erik Skogstad when Service Level Agreements SLAs are worked out A SLA can contain requirements relating to for example response time and synchronization time related to amount of data It could also be interesting to observe the average amount of data sent per synchronization As long as the pricing scheme is not fixed this can be used for predicting revenue possibilities The log file had information regarding synchronization time consumption during the system testing Typically 1 3 modified items were transferred Table 7 1 lists the values observed for setup time and sync time for the two devices Table 7 1 Synchronization time consumption Sync time could be read from the log file by checking first and last timestamp for the ongoing session Total time was calculated by observing the time passed from the moment the user started the synchronization until the screen displayed that synchronization was completed Setup time is then the difference between total time and sync time Mobile phone 4 5 seconds 5 6 seconds 9 11 seconds PDA 6 seconds 10 seconds 16 seconds As the table shows the duration time for synchronizing the PDA is higher than for the mobile phone The PDA used a WLAN connection and the mobile phone connected with GPRS The difference in synchronization time consumption could be due to the fact that the mobile phone sent the data in plain u
68. nversation Henry thinks to himself that he might need to call her back at a later time and saves her contact information on his own mobile phone Table 4 2 Use case 2 Contact list lookup Use case description The user searches for a person that has a particular role title or group department membership Actors Employee Flow 1 The user logs on the central server 2 The user chooses to search for a contact 3 The user specificies the title role of the person he is looking for and or what group department he she belongs to This information can be chosen from a list The user indicates if the person must be available at the present time no appointments in the calendar The server returns the search results The user chooses one of the persons to save locally Requirements e Central database must include role title group department membership etc e It shall be possible to display only available people i e persons who do not have any appointments in their calendar at the time of the lookup e From the list of results it shall be possible to save contact information locally 21 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad 4 1 3 New contact information Michael and Sarah are new consultants in Top Consulting and receive their own PDA and mobile phone These devices are being synchronized so that the company s
69. obally Unique Identifier Hypertext Transfer Protocol Hypertext Transfer Protocol Secure International Mobile Equipment Identity Internet Service Provider JavaServer Pages Locally Unique Identifier Mobile Repository System Open Mobile Alliance Personal Digital Assistant Personal Information Manager Service Level Agreement Strengths Weaknesses Opportunities and Threats Synchronization Markup Language Web based Distributed Authoring and Versioning Wireless Local Area Network Wireless Markup Language Uniform Resource Identifier Extensible Markup Language MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Abstract This thesis presents a net centric solution that offers users the possibility to synchronize their contact and event data with a server and access data from a central data repository independent of the location of the user The data in this repository can be retrieved and modified through user interfaces for mobile phones PDAs and computers The devices synchronize their data using the SyncML synchronization protocol an open standard for data synchronization The server used is the Sync4j SyncServer and it is a Java based SyncML server that can be used with any SyncML enabled client Since synchronization is a central aspect the report will present basic principles for data synchronization It will also provide a technical overvie
70. personal contacts and calendar can be synchronized with his her personal Exchange account To make this possible an Exchange Contact SyncSource and an Exchange Calendar SyncSource must be added in SyncAdmin to integrate the SyncServer with the Exchange datastore This procedure is explained in detail in Appendix C 5 2 2 Authentication For the user to be able to synchronize he she must be authenticated Each user must be added to the list of users in the SyncServer In addition the user must be able to synchronize using different devices All devices must be added to the list of devices in the SyncServer Finally a pairing of users and devices must be added A lt gt combination is referred to as a principal 5 2 3 File system database As mentioned earlier the SyncServer includes its own file system database for storing data Each file constitutes a data item and the file is in XML format Figure 5 2 gives an example of a file representing a contact SOT MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad lt xml version 1 0 encoding ISO 8859 1 lt contact gt lt EmaillAddress gt vbrown mail com lt EmaillAddress gt lt BusinessTelephoneNumber gt 1 329 5864389 lt BusinessTelephoneNumber gt lt FirstName gt Vincent lt FirstName gt lt NickName gt lt NickName gt lt Title gt lt Title gt lt JobTitle gt CEO lt Job
71. r spring 2005 at the Department of Telematics in collaboration with Telenor R amp D I would like to thank professor Lill Kristiansen and supervisors Anne Marte Hjemas and Frode Flegstad both from Telenor R amp D for valuable ideas and comments throughout the work period A thank also goes to the users of the Sync4j users mailing list for their help troubleshooting various technical problems Trondheim 13 June 2005 Bent Erik Skogstad MRS Mobile Repository System data synchronization and storage Master s thesis by Bent Erik Skogstad Table of contents ada D Ya CE pA I TABLE 5 II LIST UT UENS IV LIST OF TABLES V ABBREVIATIONS E VI ABSTRACT o M VII 1 INTRODUCTION 1 1 1 BACKGROUND AND MOTIVATION dude cenit 1 1 2 SCOPE AND LIMITATIONS vende Tec ceu RE GE 1 13 THESIS QUTLINE 1 26 RR RE EO E ids 2 2 DATA SYNCHRONIZATION PRINCIPLE G cssccssssssssscsssscsssscssscesssssssssesssssssssssnassssscsss
72. re listed below The role decompositions shown in Figure 6 5 still apply except that in this case Telenor does not make use of a third party Thus the Retailer and the 3 Party in the figure can be merged together End user Employer Customer Company Connectivity provider Telenor Telenor Mobil Synchronization provider Telenor Business Solutions Datastore provider Telenor Business Solutions Retailer Telenor Business Solutions 6 3 3 Public service For the least demanding customers the public service could be satisfactory The customers either small companies or individuals purchase or subscribe to standard non customizable solutions from a retailer The retailer itself can host the synchronization server and datastore or it could make use of third party service providers for these purposes Figure 6 6 illustrates the roles associated with the retailer and the customer As for the internal service the customer does not have any specific roles but is included in the figure to indicate its business relationship with the retailer 49 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Retailer Operations amp Maintenance Figure 6 6 Retailer and customer roles for the public service scenario First note that Figure 6 6 illustrates an example of the retailer providing all the services itself without the use of a third part
73. retation and handling of the SyncML protocol Other synchronization protocols may be added The server layer is the implementation of the synchronization server The application layer implements the server s interaction with external environments The framework implements and provides services and abstractions used by different layers to implement the component they are built of The most important of these services are Core SyncML representation and protocol configuration framework logging framework SyncML DS engine framework security framework and other commonly used utilities For additional details the reader 15 referred to 1 Transport Layer Protocol Layer Server Layer Application Layer Figure 3 6 Sync4j SyncServer layered architecture from 1 In addition to being a layered architecture the SyncServer has a modular design Table 3 1 presents the main modules that build up the Sync4j SyncServer 16 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Table 3 1 Sync4j SyncServer modules Sync4j Engine The core of the SyncServer Contains synchronization logic needed for e identifying sources and destinations of datasets to be synchronized e identifying what data needs to be updated added or deleted e determining how the updates must be applied e conflict detection and resolution Transport Layer module Implements the transpor
74. rformed It would generate a lot of network traffic if there are a substantial amount of users that synchronize every time there is a minor change to an item in the datastore The users will be able to initiate synchronization by themselves as they wish but automated schemes for synchronizing at regular intervals could be a desired solution This report only focuses on manual client initiated synchronization amp GE greater than or equal to amp LT less than 4 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad In this solution there is only one instance of the SyncServer and this could quickly become a bottleneck in a system with a great number of concurrent users This is also a reliability issue and the reader is referred to the next chapter 7 3 Reliability In the current installation Sync4j is running on a single server and the organization s central data is stored on this server This is therefore a many to one topology as described in chapter 2 6 2 and the server might be a system bottleneck Additionally if the server encounters a failure and the data is lost there is no way to retrieve it For redundancy purposes there must be one ore more additional servers that store a copy of the database for example topologically organized as a cluster of servers which replicate between each other see chapter 2 6 4 For increased reliability these
75. ring synchronization packages are logically exchanged between the entities 2 A logical package can be partitioned into multiple physical messages A SyncML message is specified using XML The message header includes source target routing session and authentication MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad information The body is a set of SyncML commands identifying synchronization operations such as add delete replace search status etc Each command refers to specific data items The SyncML commands are listed in 5 Figure 3 2 shows an initialization SyncML message Lines 2 to 14 form the header and lines 15 to 26 constitute the body The header contains DTD and protocol version information hhsession ID message ID target and source information crea element lines 9 to 12 indicates user credentials in this case using basic authentication The lt MaxMsgSize gt element indicates the maximum SyncML message size that the client can receive The lt Alert gt lines 16 to 24 tell the server to synchronize with the database referred to in the server URI exchange contacts with the database EriPBDB on the client device The Anchor line 22 is used to check whether the last synchronization terminated correctly 4 After a successful synchronization the Next anchor is stored and on the next session this value is sent as
76. s When John has found an available time slot the system will make sure that Susan s and Tom s mobile devices is synchronized with the server and that they are alerted about the meeting Both Susan and Tom have to confirm the appointment 22 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Table 4 4 Use case 4 Add a new appointment involving other people Add a new appointment involving othe Use case description The user is to set up a meeting with co workers and uses the system to find an available time slot for the meeting Actors User A sets up meeting user B participates in meeting Flow 1 User A logs on to the system 2 User A chooses to add a new event in the calendar 3 User A indicates that other people will be participating and chooses these user B from a list possibly a search 4 An overlapping view of user A s and B s calendars is displayed to user A and user A chooses a time period that is suitable for both user A and user B The status of the appointment will be Pending 5 The server will issue a Server Alert to user B s mobile device to initiate synchronization with the server User B synchronizes his calendar with the server User B receives a message that a new appointment awaits acceptance User B accepts and synchronizes once again with the server o N Oo User A receives a m
77. s responsible for processing the HTTP GET and POST variables and makes sure that the correct JSP page is displayed Figure A 3 shows an excerpt that makes sure that the user is pointed to the getvcard jsp file when the GET POST variable task equals vcard 63 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad public final static String TASK VCARD VCARD public final static String VIEW VCARD getvcard jsp protected void processRequest HttpServletRequest request HttpServletResponse response throws ServletException IOException else if task equalsIgnoreCase TASK VCARD viewContact request next VIEW VCARD moveToNextView request response next Figure A 3 processRequest method A 2 WML For the mobile phone interfaces the JSP files have been rewritten in WML format main jsp is also changed to set the content type to text vnd wap wml files related to the mobile phone interface are located on the enclosed CD in the folder src wap The only change to the PDIServlet code is in the updateContact method If a user modifies a contact using his her mobile phone the fields that are not included in the WML page salutation middle name suffix nickname note and birthday would be reset i e blank The processing of these fields was therefore deleted from the updateContact method for the mobile phone interfac
78. server modified on the server Modify a contact on the server and initiate The modified contact is also OK OK synchronization from the device modified on the device T15 Add contact 39 MRS Mobile Repository System data synchronization and storage Master s thesis by Bent Erik Skogstad Add a new contact on the device and synchronize The new contact is also added OK OK with the server on the server Add a new contact on the server and initiate The new contact is also added OK OK synchronization from the device on the device T16 Delete contact Delete a contact on the device and synchronize The contact is also deleted from OK OK with the server the server Delete a contact on the server and initiate The contact is also deleted from OK OK synchronization from the device the device T17 Transfer of events from server Start out with an empty calendar on the device the items on the server OK OK and synchronize with the events on the server displayed in the device s calendar T18 Modify event Modify an event on the device and synchronize The modified event is also OK OK with the server modified on the server Modify an event on the server and initiate The modified event is also OK OK synchronization from the device modified on the device T19 Add event Add an event on the device and synchronize with The new event is also added on OK OK the server
79. servers should be geographically distributed in case of a network failure As for the Exchange server the same problem exists but in this case the problem is not as critical The Exchange server stores the users private contacts and calendar and in case of a server failure the users will most likely have the items stored on their mobile devices as well Hence they would only need to synchronize a device with the server once it is up and running again retrieving the lost data 7 4 Performance Synchronization time is related to the network connection and amount of data to be synchronized Time requirements vary according to user needs For instance a mobile device can synchronize when a person arrives at work in the morning and he she can do something else while waiting for the synchronization to finish But there may be other uses that involve stricter requirements to synchronization time Synchronizing only a subset of the data as discussed in chapter 7 2 will also have positive impact on the synchronization time The SyncServer has an option to log all events relating to a synchronization attempt With the Log all option detailed logs containing time operations and the content of the SyncML messages are displayed This log file could be used to generate useful data on the synchronization time content length of messages etc This type of data can be very useful 55 MRS Mobile Repository System Net centric data synchro
80. so be discussed and three scenarios for deploying the service are investigated internal network internal service and public service These scenarios are accompanied by an illustrating case 6 1 Roles If the Mobile Repository System shall be deployed in the market there are many actors needed to realize the service These actors need to cover certain roles as described below End user The end user is the person who operates the mobile device and synchronizes its data with the server datastore Customer The customer role is the instance that pays for the service in question The payment could consist of the charge of the transportation and storage of data subscription fee etc Connectivity provider The connectivity providers will provide the users with Internet access This could be an ISP or a mobile phone operator offering Internet access through e g GPRS Synchronization provider The synchronizing instance is typically the synchronization server In the case of Mobile Repository System this is the Sync4j SyncServer This server could be installed at and operated by the customer or it could be left to a third party Datastore provider The datastore provider facilitates the storage of the central company data relevant to synchronization The datastore could reside along with the synchronization server or it could be a separate instance stored in a remote location The datastore provider can therefore be the
81. some form of authentication mechanism is added If only users registered in the Sync4j SyncServer are allowed to access the MRS then it would be preferable to link this with the user database for Sync4j Then the user logs on to the MRS with the same username and password as he she uses for synchronization Synchronizing with the Exchange server requires that the Exchange user is added to the SyncServer and that there exists a mapping between the user and the device he she is using a so called principal as explained in chapter 5 2 2 The SyncServer uses basic authentication to verify the user s credentials 1 a Base64 encoded representation of username password 15 transmitted 5 In addition SyncML protocol requires support for 5 digest access authentication Then the server issues a nonce and calculates a hash of the concatenation username password nonce This authentication scheme is more secure as the nonce will change the authentication hash in each message preventing replay attacks Currently MD5 authentication is not supported in the Sync4j implementation For improved security it could also be a good idea to use HTTPS as a transport protocol instead of HTTP 7 7 Future work There are many issues mentioned in this and previous chapters that need to be resolved To summarize the following list points out areas that could be useful Authentication of users accessing the MRS using web or WAP interfaces
82. ssed in the output pipeline and builds a HTTP response 7 Finally the HTTP message is sent back to the device 3 3 The vCard format vCard is an electronic representation of a person s business card A number of information types can be specified The latest vCard version is version 3 0 specified in 7 The version used in the Sync4j implementation is the previous version version 2 1 and therefore this section will refer to this version vCard version 2 1 is specified in 8 A vCard 2 1 representation begins with BEGIN VCARD and VERSION 2 1 and ends with END VCARD Table 3 2 only lists a subset of the information types defined in 7 but the most important types in the author s opinion are covered Table 3 2 vCard information types Name N Surname First name Middle Salutation Suffix Formatted name FN Formatted name Organization ORG Company Department Job title TITLE Job title Telephone numbers TEL WORK VOICE business phone number TEL HOME phone number TEL CELL VOICE mobile phone number TEL HOME FAX home fax number Work address ADR WORK Street City County Postal code Country Home address ADR HOME Street City County Postal code Country Role ROLE Role Birthday BDAY Birthday E mail EMAIL PREF INTERNET e mail address Revised REV Date of revision 18 MRS Mobile Repository System Net cen
83. sssssssssnessseses 3 2 1 HANDLING 3 2 2 CHANGE DETECTIONS 3 23 4 2 3 1 CONFLICTS essct RUSO NURSES UI RUE ERN Le EROS 4 239 22 Conflict ete TOTIS ERN REEE 2 2 3 3 Conflict FOSOIUTIORL s NR NN TENA HORIS 2 2 4 SLOW VERSUS FAST SYNCHRONIZATION e FORSE LEER 6 25 USAGE icti EE DRE TS ODORE nya ERR RE ERE dante 6 231 p S 6 232 ctetu ten d tot 6 2 5 3 uM Im 7 2 6 TOPOLOGIES Pe 7 2 6 1 O7 STR T ARR 7 202 M hy 10 DRe sisse ue iN DUI E 8 203 E Ra ee erben Debe Patet gue eda 8 204 Cluster and Debe abeo dee cbe ee ERE 8 3 TECHNOLOGY OVER VIEW 10 10 BLE SYNCMEG AUDI AEEA 11 Jd Synchronization types
84. stem This involves a description of the server user interfaces and functionality for both web and WAP as well as system tests Chapter 6 contains business considerations for various service realization scenarios focusing on describing business roles Chapter 7 discusses important topics related to the system implementation These topics are architecture scalability reliability performance openness and system interface considerations This chapter also points out areas for future work Chapter 8 presents conclusions MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad 2 Data synchronization principles There are a number of issues relating to data synchronization that need to be considered The most important of these issues will be presented in this chapter and these include ID handling change detection conflict detection and resolution slow and fast synchronization and synchronization topologies and types 2 1 ID handling The data records need to be uniquely identified by an identifier The identifiers of the records residing on the central server are called GUIDs globally unique identifiers and the record identifiers on the various devices are called LUIDs locally unique identifiers 1 These identifiers point to the same items but are not necessarily the same on all devices and server and for that reason the server needs to have a mapping table
85. stomer purchases the service from a retailer The retailer itself can host the synchronization server and datastore or it could make use of third party service providers for these purposes The retailer and or the third party service provider are responsible for the operations and maintenance of the service Figure 6 5 uses the scenario with the third party service provider as an example Note that all the roles associated with the third party could be the sole responsibility of the retailer 47 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Retailer Operations amp Maintenance Deployment ystem integration 3rd party Deployment Operations amp Maintenance ystem integration Figure 6 5 Retailer customer and third party roles for the internal service scenario Now the customer is not directly involved in hosting and operations maintenance and the customer is only included in the figure to illustrate its business relationship with the retailer Note that it is the retailer that has a business relationship with the third party service provider the customer only has an indirect relationship through the retailer There are a number of overlapping roles in this scenario The third party service provider most likely plays an active role in the deployment and system integration phases It would also be necessary that the
86. synchronization and storage Master s thesis by Bent Erik Skogstad 3 Technology overview In this chapter central technologies formats and implementations will be described in further detail The SyncML specification which is an open specification for data synchronization is presented first The open source initiative Sync4j implementing the SyncML protocol is a central part of the work done in this assignment and will be described in the following chapter Finally the standard formats for representing contacts and calendar events vCard and iCalendar are introduced 3 1 SyncML The SyncML Initiative was founded in February 2000 by the founding sponsors Ericsson IBM Lotus Motorola Palm Psion and Starfish 2 The first version of the specification was released December 2000 The initiative has now consolidated into the Open Mobile Alliance OMA and it is separated in two working groups Device Management Working Group and Data Synchronization Working Group 3 This assignment will concentrate on data synchronization and will not focus on device management The two fundamental parts of this specification are the SyncML Synchronization Protocol 4 and the SyncML Representation Protocol 5 The Synchronization Protocol describes the sequence of packages that applications must exchange in order to communicate changes to each other The Representation Protocol describes the syntax for specifying changes an application has made
87. synchronize the contact list on a PDA with the server R3 2b The user shall be able to synchronize the calendar on a PDA with the server R4 1a The user shall be able to modify a contact item in MRS using a mobile phone R4 1b The user shall be able to modify a calendar item in MRS using a mobile phone R4 2a The user shall be able to modify a contact item in MRS using a PDA R4 2b The user shall be able to modify a calendar item in MRS using a PDA R4 3a The user shall be able to modify a contact item in MRS using a computer R4 3b The user shall be able to modify a calendar item in MRS using a computer R5 1a The user shall be able to add a contact item to the MRS using a mobile phone R5 1b The user shall be able to add a calendar item to the MRS using a mobile phone R5 2a The user shall be able to add a contact item to the MRS using a PDA R5 2b The user shall be able to add a calendar item to the MRS using a PDA R5 3a The user shall be able to add a contact item to the MRS using a computer R5 3b The user shall be able to add a calendar item to the MRS using a computer R6 1a The user shall be able to delete a contact item from the MRS using a mobile phone R6 1b The user shall be able to delete a calendar item from the MRS using a mobile phone R6 2a The user shall be able to delete a contact item from the MRS using a PDA R6 2b The user shall be able to delete a calendar item from the MRS using a PDA R6 3a The user shall be able to delete a contact
88. t item will be added to the search results JSP pages The JSP pages included in the demo have also been modified Table A 1 displays the pages in use 62 MRS Mobile Repository System data synchronization and storage Master s thesis by Bent Erik Skogstad Table A 1 JSP files add jsp Add a new contact addca jsp Add a new event getical jsp Get the iCalendar representation of an event getvcard jsp Get the vCard representation of a contact main jsp Main page loads the other pages menu jsp The front menu results jsp View contact search results resultsca jsp View event search results search jsp Contact search page searchca jsp Event search page view jsp View contact details viewca jsp View event details menu jsp is the front menu and all other JSP files are displayed through main jsp see Figure A 2 To make the user able to download an iCalendar or vCard the content types are set accordingly String main request getParameter main String task request getParameter task if task null task equalsIgnoreCase vcard response setContentType text x vcard else if task null 6868 task equalsIgnoreCase ical response setContentType text calendar gt lt jsp include page lt main gt gt Figure A 2 main jsp for web interface The method processRequest i
89. t a pilot will be run for the employers at St Olav s Hospital Challenges facing this pilot will be that the employers will be using IP telephones and MDAs in their daily practice but outside the hospital area they will use mobile phones MRS must be able to handle the fact that a user has several different types of mobile terminals but that all of them should have the same contact information The assignment shall also discuss architecture scalability reliability performance and openness Business models shall be developed including actor role analyses dealing with such a service realized in an internal network as an internal service delivered by Telenor or a third party or as a regular public service delivered by Telenor or a third party SWOT analysis and system interface considerations especially regarding transport through closed networks shall be worked out Start date 19 January 2005 Deadline 15 June 2005 Submission date 13 June 2005 Department Department of Telematics Supervisors Anne Marte Hjemas and Frode Flegstad Telenor R amp D Trondheim 22 February 2005 Lill Kristiansen Professor MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Preface This thesis concludes my Master of Science education in Communication Technology at The Norwegian University of Science and Technology NTNU in Trondheim The thesis was performed throughout my 109 semeste
90. t fields Click on a contact listed in The contact details page for this contact is OK OK OK search results displayed Figure A 9 T2 vCard representation Click Save vCard Download box for the contact s vCard OK Not OK representation web Contact is downloaded OK and the user is prompted to add it to the contact list phone Search for contacts Go to Contact search and Only contacts that contains the entered data in OK OK OK enter information in relevant the corresponding fields are displayed fields Click Search T4 Modify contact View the contact details The contact details are listed again with all the OK OK OK again and edit the text in all modified fields displayed correctly the fields Click Modify Go to Contact search and Search results page is displayed with the OK OK OK search for the contact just recently modified contact on the list modified Click Search Click on the contact The contact details page is displayed with the OK OK OK modified information T5 Delete contact Click delete Confirmation dialog box will appear web OK OK OK Back to menu screen phone Confirm dialog box web Menu screen is displayed OK OK N A Go to Contact search and Search results page is displayed with the OK OK OK search for the contact just recently deleted contact not on the list entered Click Search T6 Add contact Click on link Add contact Add contact page is displayed Figure A
91. t specific binding of SyncML SyncML module Responsible for encoding and decoding SyncML messages Protocol Implements the SyncML synchronization protocol Services module Provides horizontal services such as authentication security configuration logging etc SyncSources Facilitates integration with external and legacy systems 3 2 2 Execution flow When a device sends a request to the server the execution flow is as shown in Figure 3 7 Figure 3 7 Execution flow from 1 The figure shows the execution flow of a client request This request is processed by the SyncServer and a response is sent back to the client 1 The device sends the request and the HTTP handler processes it e g associating it with an ongoing session The processed request is sent to the SyncServer 2 The input pipeline of the SyncServer is a preprocessing instance that can be customized to process the messages according to specific application needs gt 17 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad 3 The processed message is sent to the server engine which does the actual synchronization processing 4 The engine may use custom sync sources to access external data stores if necessary The engine then builds a response that goes through the output pipeline for postprocessing 6 The HTTP handler takes the messaged proce
92. tact s role Telephone number The user can enter a string that is compared to the contact s home phone number business phone number cell number and home fax number The entered number will be cleaned i e any other characters than digits will be removed from the string This implies that the string entered will be handled as a string of consecutive digits e g 1 123 456 78 will become 29 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad 112345678 The same cleaning procedure is applied to the contact s various phone numbers and the entered string is compared to each of the contact s phone numbers If it is a substring of at least one of these phone numbers a match occurs Address A match occurs when all the words entered are substrings of the concatenation of the contact s work address street postal code city state and country The entered search words can also be substrings of the concatenation of the contact s home address street postal code city state and country 5 3 2 Add new contact The user also has the option to add a new contact to the central company database This option includes more fields than the search option A partial view of the add contact interface is shown in Figure A 7 The text fields are divided in three departments General Personal and Business The fields are listed in Table 5 1 but further details about them are
93. te the entire event listing An iCalendar representation of the event can also be downloaded Figure A 13 shows the details of a sample event 5 4 WAP user functionality An interface for mobile phones has also been developed using the same skeleton The JSP pages have been rewritten in WML 13 for this purpose For usability and to limit the amount E MRS Mobile Repository System data synchronization and storage Master s thesis by Bent Erik Skogstad of data transferred this interface is somewhat lighter than the web interface not including as many text fields Telenor MAS contact che Add contact Event search Add event Figure 5 3 WAP front menu 5 4 1 Contacts The WAP contact interfaces are displayed in Figure 5 4 UE MHS Telenor MAS F R CONTACTS iordmann mith Mike A H rM Figure 5 4 Screen photos of contact interfaces 1 Search for contacts 2 Search results 3 Contact details top of page 4 Contact details bottom of page 5 Add contact 33 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Table 5 2 lists the attributes input text fields for the various contact interfaces The processing and content of these fields are identical to the web interface For the description of these fields see chapters 5 3 1 5 3 3 Table 5
94. the server Add an event on the server and initiate The new event is also added on OK OK synchronization from the device the device T20 Delete event Delete an event on the device and synchronize The event is also deleted from OK OK with the server the server Delete an event on the server and initiate The event is also deleted from OK OK synchronization from the device the device The PDA tests for deleting items T16 and T20 occasionally experienced read timeouts when synchronizing and the PDA had to be reset This was quite annoying and the reason for this error is unknown This never occurred with the mobile phone but quite frequently on the PDA so it is reason to believe that the problem is related to the SyncClient PIM Pocket PC client Another observation from the testing is related to displaying contacts names When adding a new item on the mobile phone e g Hans Olsen the name shown in Outlook Web Access was on the format Hans Olsen i e the first and last name has been switched On the other hand if the contact s details are viewed the first and last names are correct Hence this is a problem with the display name Also the mobile phone used does not separate between first name and last name People with two or more first names e g Hans Erik Olsen will be added with first name Hans and last name Erik Olsen in Exchange The mobile phone gives the possibility to set the synchronization sequence to last name
95. to its data Figure 3 1 shows the main elements of the SyncML Framework 10 MRS Mobile Repository System data synchronization and storage Master s thesis by Bent Erik Skogstad SyncML Framework Sync Engine application amp md syncml SyncML XML Objects Transport 1 e g HTTP WSP OBEX Figure 3 1 SyncML Framework redrawn from 5 The main elements of the SyncML framework and the supporting entities applications synchronization engines and synchronization agent App A is the server application that provides the synchronization service for client applications App B The synchronization engine is a logical entity that keeps track of changes made by the server application and it also has methods for detecting and resolving changes retrieved from the clients 2 The synchronization agent is responsible for the generation and processing of SyncML packages The Sync Server Agent manages the Sync Engine s network access and communicates the synchronization operations to from the client application through the SyncML I F 5 This is the interface towards the SyncML Adapter which the originator and recipient of SyncML formatted objects use to communicate with each other The SyncML Adapter also interfaces with the transport layer On the client side the Sync Client Agent accesses the network as well as the SyncML Adapter through the SyncML I F 3 1 1 SyncML messages Du
96. tp download forge objectweb org sync4j sync4j syncserver developer guide 2 2 pdf U Hansmann R Mett l A Purakayastha P Thompson SyncML Synchronizing and Managing Your Mobile Data Upper Saddle River NJ Prentice Hall 2003 ISBN 0 13 009369 6 Open Mobile Alliance OMA Technical Section Affiliates SyncML http www openmobilealliance org tech affiliates syncml syncmlindex html The SyncML Initiative SyncML Sync Protocol version 1 0 1 2001 http www openmobilealliance org tech affiliates syncml syncml_protocol_v101_2001 0615 pdf The SyncML Initiative SyncML Representation Protocol version 1 0 1 2001 http www openmobilealliance org tech affiliates syncml syncml_represent_v101_2001 0615 pdf The Sync4j Project home page http sync4j funambol com F Dawson T Howes vCard MIME Directory Profile RFC 2426 September 1998 http www ietf org rfc rfc2426 txt versit Consortium vCard The Electronic Business Card Version 2 1 September 18 1996 http www imc org pdi vcard 21 Dawson D Stenerson Internet Calendaring and Scheduling Core Object Specification RFC 2445 November 1998 http www ietf org rfc rfc2445 txt The Sync4j Project download page http sync4j funambol com main jsp main download stable The Sync4j Project Sync4j SyncServer Administration Guide 04 05 05 http download forge objectweb org sync4j sync4j syncserver admin guide 2 2 pdf The Sync4j Project Sync4j SyncConnector Exchange
97. tric data synchronization and storage Master s thesis by Bent Erik Skogstad An example vCard is shown in Figure 3 8 BEGIN VCARD VERSION 2 1 N Nordmann Kari A Ms d y FN Nordmann Kari A NICKNAME Karri DR HOME Havnegata 1 0s10 0s10 0123 Norway DAY 1950 01 01 EL VOICE HOME 4712345678 A B TEL CELL 4734567890 T TEL FAX HOME 4723456789 E MAIL INTERNET kari nordmann sykehuset no ADR WORK Sykehusgata 1 0s10 0s10 0123 Norway ROLE Coordinator TITLE Secretary ORG The Hospital Administration TEL VOICE WORK 4 745678901 NOTE Eksempelperson REV 20041020T142542 END VCARD Figure 3 8 Example vCard 3 4 The iCalendar format iCalendar is an electronic representation of events A number of information types can be specified An iCalendar representation begins with BEGIN VCALENDAR and BEGIN EVENT and ends with END VEVENT and END VCALENDAR The information types in the example iCalendar in the example iCalendar in Figure 3 9 are a subset of the information types defined in 9 but the most important types in the author s opinion are covered The fields are reasonably self explanatory and will not be described in further detail BEGIN VCALENDAR BEGIN VEVENT CATEGORIES Internal DESCRIPTION Staff meeting LOCATION London SUMMARY Meeting DTEND 20050805T080000Z 5 20050805 0600002 1 UID 1115730846226
98. ts and all events that have occurred in the past SyncML specifies a CGI script search filter 5 that can be appended to the target LocURI to perform selection filtering Unfortunately this is not implemented in the current release of Sync4j CGI scripting could be one approach to synchronize only a subset of the data e g just choosing today s calendar events excluding all earlier later events contacts notes tasks and other data An example is illustrated in Figure Telk lt Target LocURI calendar DTSTART amp GE 20050601T000000 amp AND DTEND amp LT 20050608T000000 LocURI Target Figure 7 1 target address filtering based on 5 In this example calendar database events located in the folder calendar are filtered so that just events that start on or after June 1 2005 and end no later than June 8 2005 are returned A typical file created in the file system database has a size of a few hundred bytes up to a couple of kilobytes Thus storing contact and calendar information would not require much disk space even in a large organization with a considerable amount of external contacts and employees In addition to the amount of data associated with synchronization the frequency of synchronizations will affect scalability The frequency of changes to the datastore and the network traffic associated with propagating these changes to the relevant users will influence how often synchronization should be pe
99. ure A 12 Add event e Figure A 13 Event details Mobile Repository System Mozilla Firefox DER File Go Bookmarks Tools Help amp LJ http 129 241 219 132 pimweb main jsp main main amp db calendar amp demo calendar amp task search Go Search for event Subject Starting date after dd mmiyyy 1 Starting date before ddirm yyy Eventtype Location Description Display only future events 2 Figure 10 Search for event 69 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad Mobile Repository System Mozilla Firefox Edit View Bookmarks Tools Help B OB 9 htpi29 241 219 132 pimweb main jsp _ resource Search results Select an event or create a new one 2005 08 05 08 00 Meeting Figure A 11 Event search results Mobile Repository System Mozilla Firefox Eile Go Bookmarks Tools Help G 6 0 hipitzo 241 219 132 pimweblmain jsp mainemain amp dbecelendar amp demo celendar amp taskeadd e Add event Subject Starting date dd mm yyyy Starting time hh mm 2 Ending date ddimmiyyy EN i Ending time hh mm Eventtype Location Description These fields are mandatory Figure A 12 Add event 270 MRS Mobile
100. vice The business relationships displayed in Figure 6 2 are valid for all these scenarios but the roles of an actor in one scenario might be different from the actor s roles in another scenario Especially the customer role and the retailer role are subject to change 6 3 1 Internal network In this case the synchronization server and optionally the storing of data are located in the internal network see Figure 6 3 This could be beneficial for relatively large companies A 45 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad retailer can offer a customized solution to be installed as a part of the company s internal network The synchronization server must be accessible from outside the internal network Company intranet Exchange server Figure 6 3 Service realized in an internal network Possible role decompositions of the retailer and customer are drawn in Figure 6 4 Retailer Operations amp Maintenance Deployment vstem integration Customer Operations amp Maintenance Figure 6 4 Retailer and customer roles for the internal network scenario What makes Figure 6 4 different from Figure 6 3 is that the customer now is hosting the synchronization and datastore server Otherwise the retailer will assist the customer in all the aspects previously explained The customer can perform some operations and m
101. w of SyncML and the Sync4j implementation The main implementation focus is directed towards user functionality for adding modifying deleting and searching for contacts and events in the central repository The report will describe these features for the different device types Further the report will identify roles that need to be covered when deploying the service in a market and it will also look at business relationships between these roles Three scenarios for deploying the service are investigated and from these one can observe how the different roles change depending on how the service is realized The scenarios will look at the service realized in an internal network as an internal service offered by a retailer or a third party or as a public service and these scenarios are illustrated by small cases to point out the relations between actors and roles Finally aspects concerning architecture scalability reliability performance openness and system interface are looked into vii MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad 1 Introduction The introduction chapter will give a brief description of the background and motivation for this master s thesis pointing out why there is a need for net centric data synchronization and storage Scope and limitations for the thesis will be defined and finally the chapter outline of this report is
102. way TEL CELL 4799608303 EMAIL INTERNET benterik stud ntnu no N END VCARD PF Ui V Data Item 23 Replace 24 Sync Figure 3 4 Replace command from log file If the item is deleted on the server side the tag lt Delete gt in Figure 3 5 will be included in the Sync section lines 5 to 8 The lt Target gt lt LocURI gt tag is a reference to the item to be deleted on the mobile phone line 7 1 Sync 2 CmdID 3 CmdID 3 Target LocURI EriPBDB LocURI Target 4 lt Source gt lt LocURI gt exchange contacts lt LocURI gt lt Source gt lt Delete gt 6 CmdID 2 CmdID 7 lt Item gt lt Target gt lt LocURI gt 0000000003A3 lt LocURI gt lt Target gt lt Item gt 8 lt Delete gt 9 Sync Figure 3 5 Delete command from log file das MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad 3 1 2 Synchronization types 4 specifies seven different synchronization types Two way synchronization The client and the server exchange information about modified data with the client sending its modifications first Slow synchronizatoin With slow sync not just the modified data are compared but all items are compared on a field by field basis Refresh synchronization from client only The client s
103. y service provider A third party could of course also be involved as for the internal service scenario As can be seen from the figure the retailer is somewhat lighter than previously illustrated The system integration deployment and consulting roles are all removed This is due to the fact that the public service is more standardized and not as customizable The retailer offers a package featuring synchronization and storage for use with specific software and systems supporting certain devices but if the customer has needs beyond what is included and supported in the public service it must choose either the internal network or the internal service solution Case illustration John Doe would like to have access to his contacts and calendar information from any location using different devices In case he loses his mobile phone this solution would also function as a backup of his data Telenor as the retailer offers a standard solution directed towards individuals and small businesses that offer this functionality Telenor will be the synchronization provider and the datastore provider and it can also be John Doe s connectivity provider both as an ISP and as a mobile phone operator offering GPRS access Telenor Mobil Telenor requires a monthly subscription fee for offering this service to Mr Doe In addition revenue is generated by offering connectivity 50 MRS Mobile Repository System Net centric data synchroni
104. zation and storage Master s thesis by Bent Erik Skogstad The actor role mappings are listed below The role decompositions shown in Figure 6 6 still apply End user John Doe Customer John Doe Connectivity provider Telenor Telenor Mobil Synchronization provider Telenor Datastore provider Telenor Retailer Telenor In this case one could also imagine that the datastore provider was a 34 party like Hotmail Yahoo or similar Then Telenor could for example offer a synchronization option with these 3 party datastore providers 51 MRS Mobile Repository System Net centric data synchronization and storage Master s thesis by Bent Erik Skogstad 7 Discussion This chapter discusses the current solution with respect to architecture scalability reliability performance openness and system interface considerations Finally some suggestions for future work are pointed out 7 1 Architecture The solution presented makes use of the file system database included with the Sync4j SyncServer for storing the organization s central data Each item is stored in a separate file in a folder e g contacts and calendar The users synchronize their mobile devices with the data in their personal Exchange account Although the data resides on the Exchange server the synchronization is performed via the SyncServer The reason why this architecture was chosen was mainly due to the problem of separating personal and business d

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