Cluster-based replication for large-scale mobile ad-hoc networks

Replication provides a feasible solution for improving data accessibility in highly dynamic and fault prone mobile ad-hoc environments. Efficient replica management, however, remains a challenging problem due to the inherent unreliable and unstable nature of mobile ad-hoc networks. This paper proposes a novel optimistic replication scheme, for achieving efficient consistency maintenance in large-scale ad-hoc mobile networks. Distributed hash table replication (DHTR) organizes all mobile nodes into non-overlapping clusters and builds a two-level distributed replica information directory on cluster heads to facilitate the propagation of query and update messages. DHTR also employs distributed hash table techniques to speed up the directory lookup process. Simulation results demonstrate that DHTR improves the performance with respect to update propagation in comparison with the ROAM replication system.