Enabling cooperation among disconnected mobile users

Mobile computing and workgroup computing are emerging technologies which have so far been treated independently. Current approaches to support cooperative work neglect the special characteristics of mobile environments like limited bandwidth or temporary disconnection. On the other hand, approaches to support disconnected operation in mobile environments rely on the assumption that the degree of data sharing is low, which is obviously not appropriate for cooperative work. In this paper, we utilize the COACT (COoperative ACTivity) transaction model to provide support for parallel, disconnected activities. The model incorporates the notion of resolvable, simultaneous work. We show how the COACT 'merge' algorithm reduces conflicts by exploiting operational semantics and offering consistent sequences of operations. We believe that our new approach is a viable solution to the growing demand for cooperation in mobile environments.

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