The Caelum (cid:3) Toolkit for CSCW: The Sky is the Limit y

We present a general framework for the construction of groupware and computer supported cooperative work (CSCW) applications. Examples of such applications include: multi-media and desktop conferencing, distance learning, interactive games and simulations, and collaborative computing. We provide application builders with a software development kit (SDK) that supports sharing of a variety of applications among dynamically changing groups of users. We provide a variety of eecient communication solutions, tuned towards diierent quality of service (QoS) requirements, as well as tools for maintaining consistency of distributed and replicated information in the face of faults. We exploit the group communication paradigm for dynamic discussion groups, and for keeping track of the dynamically changing set of participants. The discussion groups may be organized hierarchically, and discussion in groups may be secure. Our services are fault tolerant and scalable, and are therefore appropriate for multi-processor failure prone networks such as the Internet.