Open Hypermedia Systems Working Group

Collaboration via OHS - Scenario

Preliminaries

Authors
Jörg Haake

GMD-IPSI, Germany


Updates
Most recent: February 12, 1997


• created February 12, 1997
  

References


Other Links


• Analysis
  
• OHS mailing list discussion (when available)

Scenario Description

• multiple (equal or greater than two) co-authors are located at different sites,
• each co-author may use another hypermedia authoring environment,
• the co-authors need to share a common (but potentially distributed) hyperdocument, and
• there is a need to support both, asynchronous as well as synchronous collaboration.

Author A and author B are working on a common hyperdocument that consists of a network of nodes and links that are partitioned into two (for each author exactly one) subsets. Each subset is maintained by the respective author's hypermedia authoring environment. Now imagine the following collaboration process:

Author A works on his local partition (i.e., browses and edits the document's components)


While doing so, he might follow a link to author's B partition which is maintained by her hypermedia authoring environment (server). Thus, access to and display of "foreign" document parts/partitions must be possible.

Now, author A wants to edit a part of author B's partition (i.e., either change existing objects, or add objects)


Thus, the issue of access control occurs. Furthermore, the server of author B must now either store or at least reference objects created by the client/browser of author A.

At this time, author B enters the game by opening her browser and noticing A's presence


This means that there must be some group awareness mechanism that allows the collaborators to recognize each other's presence (and activities). This mechanism consists of awareness detection (potentially in the server) and awareness presentation (in the client/browser).

Author B now wants to join author's A editing session to coordinate their common efforts


Thus, B's browser needs a mechanism to contact A's browser and to establish a cooperative editing session. In such a session, the authors want to share a joint workspace (e.g., the workspace of author A) and a joint view (potentially some relaxed WYSIWIS presentation). For this, the coupled browsers or hypermedia environments need to translate their respective navigation commands into each other's "command language". Furthermore, the translation of different display techniques (even of a shared document) need to be supported. Additional communication channels (such as A/V or a chatbox) need to be provided.

After they coordinated their efforts, author B then leaves the joint session and starts to work on her own (in a different part of the document)


Thus, dynamic and spontaneous session creation, join and leave must be supported.

Sometimes later, author A finishes his work and quits his browser. Now, author B deletes some objects referenced by A's environment.


In this situation, one would expect some functionality that allows the communication of such changes between the different systems (either delayed or immediate) to ensure consistency.