1. Master Thesis Proposal
Building Collaborative Web Browsing and Chat into Standard Web Pages By
Patricia Ferrao
4/11/2019

2. Introduction
Casual user can browse the web and chat with a group of friends
Entirely HTTP based
No pre-registration, downloads or browser plug-ins
Login from anywhere and immediately start collaborating
Requires Internet access, a browser, session login and password
Uses only light-weight, open source technology
Works across firewalls
4/11/2019

3. Competing Products “Click To Meet” by First Virtual Communications
Uses T.120 and H.323
Corporate solution
Client browser requires plug-ins and uses Active-X components
Expensive (range of $17K to $30K)
“Cisco Collaboration Server” by Cisco
Also a corporate solution
Need their development kit to customize features
Client is browser-based, requires no downloads
Firewall friendly
What are the metrics for evaluating these products?
4/11/2019

4. Competing Products (Cont’d)
“Instant Co-Browsing” by Mitsubishi Electric Research Labs
light-weight, web-based solution
Uses Javascript, Java Servlets and DHTML
Uses client pull
Does not include chat, but includes a shared pointer
Not a distributed architecture solution
Requires that all browsable pages be part of the same domain as the Servlet application
have not seen an implementation available
New products rapidly emerging where? citations?
4/11/2019

5. What Differentiates My Solution?
Uses Pushlets (server push technology)
Distributed architecture that scales well and works across multiple client servers
Can browse across entire Internet (Web pages need not belong to the same domain as the application)
Uses only open-source technology
4/11/2019

6. System Architecture
4/11/2019

7. Client Server Registers with Directory
All Client Servers register with the Directory Server
Directory server keeps URL’s in database
Directory Server gives Backbone Server’s URL to Client Servers upon registration
Directory Server keeps track of how many clients each server has active at any given time
4/11/2019

8. Client Registers for a Session
Users determine session ID and password among themselves
Client uses Directory’s URL to initiate the service connection
Directory redirects user to Client Server with available resources
User logs in with the Client Server using session ID, password and login name
4/11/2019

9. Client Server Sets up a Session
Client Server informs the backbone that it is part of a session, and provides session ID and password
Backbone stores all active session IDs, passwords, and participating Client Server URLs in DB
Client Server keeps track of its sessions and participating clients
4/11/2019

10. Collaborative Browsing
User selects a URL to browse
Client browser retrieves web page
Client browser posts new URL to its local Client Server
Client Server provides session ID and URL to backbone server
Backbone gives new URL to all Client Servers belonging to session
Client Servers push new URL to participating clients
Client browsers retrieve and display web page
4/11/2019

11. Collaborative Chat User types text message at browser
Browser posts chat message with local Server
Client Server gives session ID, client login name, and text message to backbone
Backbone provides information to all participating Clients Servers
Client Servers push chat information to clients
Browsers display chat id-name and text
4/11/2019

12. System Technology MySQL MySQL JDBC JDBC HTTP HTTP HTTP HTTP HTTP
BackkBone Server
Tomcat, Servlet
Directory Server
Tomcat, Servlet
HTTP
HTTP
HTTP
HTTP
HTTP
Client Server
Tomcat, Pushlet
Client Server
Tomcat, Pushlet
Pushlets
Pushlets
Postlets
Postlets
Client
DHTML
Client
DHTML
4/11/2019

13. What is a Pushlet?
Java Servlet application designed by Just van den Broecke from Just Objects B.V.
Allows a web server to push information to a client browser
Pushes events to clients using Javascript
Browser uses Javascript to register for events with the Pushlet application
4/11/2019

14. Pushlet (cont’d) Client registers with Pushlet application
Application will hold on to the connection for as long as the client remains available
Pushlet will push an event to all active clients as soon as event is generated
4/11/2019

15. What is a Postlet?
Also a Java Servlet (Where is the reference? Who designs it?)
Allows a client browser to post an event to a Pushlet application
Client uses HTTP Get
Servlet does not hold up client connection
Postlet event is published to all Pushlet active clients
4/11/2019

16. Pushlet Experiment
Designed a Pushlet application in Fall 2002 for semester project
Application generates and clears events randomly every few seconds
Application pushes event information (either new event, or event clear) to all registered clients
Client-side DHTML displays events in a table, and updated the client’s browser with new information from server
4/11/2019

17. Experimental Results
Tomcat does not timeout Pushlet connections, even if information is not frequently pushed
Pushlet holds up a Tomcat client connection. If all allowable connections are held-up, no other client can connect
Suggest improvement on Pushlet as part of the thesis. What is your plan?” This can be one of main contribution.
4/11/2019

18. Client-Side Technology
Web page consists of five frames, one of which is a hidden frame
Visible frames include a status frame, browsing frame, URL frame, and chat frame
Status frame displays all active participants’ login IDs
URL frame contains a text field where a user can enter a new URL for collaborative browsing
4/11/2019

19. Client-Side Technology (cont’d)
Browsing frame displays the web page that all participants are currently viewing
Chat frame displays chat messages
Hidden frame maintains the Pushlet connection, and distributes events received from Pushlet application (status, URL, chat) to the correct frames
4/11/2019

20. Client-Side Technology (cont’d)
Hidden frame posts events (chat, URL) to the Client Server Postlet application
Chat frame gives its chat messages to the hidden frame for distribution
Browsing frame gives its URL to the hidden frame for distribution
4/11/2019

21. Signed JAVASCIPT
Javascript does not allow a frame to discover another frame’s URL unless all web pages belong to the same domain
Limitation can be overcome with signed Javascript technology
Snippet of Javacript code can be certified by a service like VeriSign
Client is presented with a certificate of authenticity, and must accept the certificate before the Javascript code can execute
4/11/2019

22. Limitations
Service requires clients to use Netscape Navigator as the browser (signed Javacript is browser-dependent)
This service may not work if there are proxy servers between clients and Client Servers (limitation of pushlets)
4/11/2019

23. Timeline Already Complete - done during Fall 2002 and Spring 2003
Master Pushlets and Postlets, Tomcat Server
Learn Javascript, Servlets and DHTML
Research the topic to learn about competing applications and technologies
Put together a detailed thesis topic
4/11/2019

24. Timeline (cont’d) In Progress – target completion October 2003
Write thesis proposal, pick a committee and present topic
Get committee approval
Put together a presentation for the network research group discussions
4/11/2019

25. Timeline (cont’d) Future – Fall 2003 and Spring 2004
Write software
Setup a test bed and test configuration
Future - complete during Summer 2004
Complete implementation and testing of application (final details)
Give demo to Dr. Chow
4/11/2019

26. Timeline (cont’d) Future - complete during Fall 2004
Write Thesis paper
Defend Thesis
Graduate!!
4/11/2019

27. Deliverables
Collaborative web browsing and text chat application software
Demo of registration process for Client Servers, Login process for clients, collaborative browsing, and collaborative chat (using two client servers, one backbone and one directory)
Thesis report
4/11/2019

28. References
Just van den Broecke, “ Pushlets Whitepaper ”, Just Objects B.V. 2002/08/05.
Alan W. Esenther, “Instant Co-Browsing: Lightweight Real-Time Collaborative Web Browsing”, Mitsubishi Electric Research Labs,
Nishanth Menon, “ Collaborative Tools for the next millennium (and beyond) “.
Microsoft, “Exchange 2000 Conferencing Server Downloadable documentation”, , May 2001.
Microsoft, “Microsoft Exchange Chat Service”, February 28, 2000.
Lewis Ward, “ WebEx MediaTone: Delivering on the Promise of Rich Media Communications”, white paper, “ , May 2002.
First Virtual Communications, “Click To Meet”,
4/11/2019

29. References (cont’d)
Sun Microsystems, “Sun Forum”,
John Fontana, “ Sun Launches IM server, integrates it with collaborative platform “, Network World, 04/10/03.
Cisco, “Cisco Collaboration Server”,
Linda Rosencrance, “Tech firms lobby for open IM standards”, June 08, 2000.
Cathleen Moore, “XMPP rises to face Simple standard”, InfoWorld, April 18, 2003.
Christopher Saunders, “A Lack of Simple Pleasures”, Instant Messaging Planet, Nov. 12, 2002.
Jabber Software Foundation, “ Jabber Technology Overview”,
4/11/2019

30. References (cont’d)
Eidelshtein Ilya and Taubkin Victor, “IRC – Internet Relay Chat”,
Elizabeth Daly, “Distributed Slide Show Tool”, University of Dublin, September 16, 2002
Ganesh Godavari , “SGFR : Secure Groupware for First Responders”, University of Colorado at Colorado Springs,
Microsoft Corp. “MSN Messenger”,
AOL Instant Messenger,
YAHOO Messenger,
The Apache Jakarta Project,
Patricia Ferrao, Event Application Using Pushlets, December 6, 2002
4/11/2019