Embed Size (px)
Citation preview
Moderated Group Authoring System for Campus-Wide Workgroups
This paper describes the design and implementation of a file system-based distributed authoring
system for campus-wide workgroups. We focus on documents for which changes by different
group members are harder to automatically reconcile into a single version. Prior approaches
relied on using group-aware editors. Others built collaborative middleware that allowed the
group members to use traditional authoring tools. These approaches relied on an ability to
automatically detect conflicting updates. They also operated on specific document types. Instead,
our system relies on users to moderate and reconcile updates by other group members. Our file
system-based approach also allows group members to modify any document type. We maintain
one updateable copy of the shared content on each group member’s node. We also hoard read-
only copies of each of these updateable copies in any interested group member’s node. All these
copies are propagated to other group members at a rate that is solely dictated by the wireless user
availability. The various copies are reconciled using the moderation operation; each group
member manually incorporates updates from all the other group members into their own copy.
The various document versions eventually converge into a single version through successive
moderation operations. The system assists with this convergence process by using the made-with
knowledge of all causal file system reads of contents from other replicas. An analysis using a
long-term wireless user availability traces from a university shows the strength of our
asynchronous and distributed update propagation mechanism. Our user space file system
prototype exhibits acceptable file system performance. A subjective evaluation showed that the
moderation operation was intuitive for students.
Ambit lick SolutionsMail Id: [email protected] , [email protected]
