Technical Report Number
The design of ad hoc mobile applications often requires the availability of a consistent view of the application state among the participating hosts. Such views are important because they simplify both the programming and veriﬁcation tasks. We argue that preventing the occurrence of unannounced disconnection is essential to constructing and maintaining a consistent view in the ad hoc mobile environment. In this light, we provide the speciﬁcation for a partitionable group membership service supporting ad hoc mobile applications and propose a protocol for implementing the service. A unique property of this partitionable group membership is that messages sent between group members are guaranteed to be delivered successfully, given appropriate system assumptions. This property is preserved over time despite movement and frequent disconnections. The protocol splits and merges groups and maintains a logical connectivity graph based on a notion of safe-distance. An implementation of the protocol in Java is available for testing. The implementation is used to implement Lime 1, a middleware for mobility that supports transparent sharing of data in both wired and ad hoc wireless environments.
Huang, Qingfeng; Julien, Christine; and Roman, Gruia-Catalin, "Relying on Safe Distance to Achieve Strong Partitionable Group Membership in Ad Hoc Networks" Report Number: WUCSE-2002-35 (2002). All Computer Science and Engineering Research.