Review

1
Architecture of Internet Based Groupware
Applications BSCW Case Study

• Review
• BSCW Users View
• Basic Architecture
• Extended Architecture

2
Limitations of the Web -1

• Limited awareness
• no idea of who else is browsing a page or
  updating it
• so no notification of changes
• Poor User Interface
• no menu bars, so cluttered UI and all operations
  a click away
• difficult to reflect changes especially at the UI
  level
• no local support for interaction as web clients
  are dumb - computation is usually on the
  server, e.g. difficult to view documents through
  the hierarchy in BSCW
• Limited Configurability/Tailorability
• again because through the server - central
  administration of user preferences

3
Limitations of the Web - 2

• Communication Limited to Client-Server - a
  request-response protocol
• no (server initiated) server-client
  communications
• no client-client communications
• Pure Centralised Architecture
• no support for distribution of information and
  computation amongst servers
• no replication across servers
• No Guaranteed Quality of Service
• bursty data
• no real-time support

4
Successful Web-based Groupware
1. BSCW 2. TCBWorks 3. CoMentor 4. WinWin 5. OU
World Wide Design Lab 6. Columbias OzWeb
hypermedia collaboration environment 7. Oulus
Web-based Inspection tools
5
BSCW - Users view
6
Common Gateway Interface
The server supporting CGI treats some HTTP
requests as calls to CGI scripts which are
invoked and handle the request usually providing
an HTML page in reply.
7
Basic BSCW Architecture
8
MetaWeb Server
This has been used to extend the Web with support
for synchronous groupware applications. The
MetaWeb server provides a event notification
service through the MetaWeb client API.
9
Extended BSCW Architecture

10
References

• 2 BSCW papers
• The World Wide Web as enabling technology for
  CSCW The case of BSCW
• Beyond Web Technology - Lessons Learnt from BSCW
• For pure Java applications - SUNs Java Shared
  Data Toolkit can be used to build groupware
  applications requiring support for synchronous
  communication. (see java.sun.com/products/java-med
  ia/jsdt/jsdt-faq.html)