Transparent Latecomer Support for Synchronous Groupware

  • Stephan Lukosch
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2806)

Abstract

In a collaborative session users may join and leave. A user who joins a session is called a latecomer. A latecomer needs the current state of the collaborative session to participate in the session. There exist different approaches to accommodate a latecomer. The runtime system can, e.g., transfer the state to the latecomer or replay how the session state was reached. If the state is maintained on a well-known server, it is quite simple to supply the latecomer with the current state. However, if the server is not available, the latecomer cannot join. To increase the fault-tolerance, the runtime system has to use a decentralized approach. In this case, race conditions must be taken into account. DreamObjects is a platform that simplifies the development of shared data objects. It supports a direct state transfer as well as a replay and lets a latecomer choose how to join a session. Both approaches are completely integrated in the runtime system, work completely decentralized, and do not block the other participants in their current work.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • Stephan Lukosch
    • 1
  1. 1.Computer Science II – Cooperative SystemsUniversity of HagenHagenGermany

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