Maintaining Group Connectivity In Dynamic Asynchronous Distributed Systems

In the context of asynchronous distributed systems with infinitely many processes, this paper studies the problem of maintaining connectivity among a set of processes forming a group in a dynamic context where (i) processes can arrive to and depart from the group and (ii) processes have a partial knowledge of other processes belonging to thegroup. In this setting we give the specification of a new problem, namelythe Dynamic Group Connectivity (DGC), we provide a few impossibility results and give a deterministic protocol solving the problem. We give, in such a dynamic context, (i) the speci¯cation of a service of reliablebroadcast showing that it is equivalent to DGC and (ii) the specification of a service of atomic broadcast and a solution based on the protocol presented to solve DGC