Research And Design On Data Replication Technology In Mobile Ad Hoc Networks

It is commonplace that the rapid advances in wireless communications, electronics and networking have resulted in a new computing pattern, mobile computing. An increasing number of new portable device (Pocket PCs, PDA, mobile phones) has become a significant part of every day life and work, leading to a decentralized wireless computing environment. Personal mobile devices may now store and process data, giving the opportunity to develop novel application. However, because of the restrictions in wireless environment, mobile data management becomes more complex than traditional environment.Data replication is one of the key technologies in mobile data management. In mobile environment especially mobile ad hoc environment, mobility, disconnections, weak connectivity, resource scarcity, diversity of networks together bring big challenges when designing a data replication system. After balancing these mobile characteristics and analyzing of some existing replication systems, we present a novel data replication topology especially for mobile ad hoc networks. A lot a strategies are involved to benefit the system: location-based clustering, optimistic mobile node voting protocol and adaptive replication ring.Further, based on this replication topology, we present a log-base reconciliation protocol which can dramatically reduce network costing, and data consistency can be easily maintained. At last, we designed an optimized algorithm for dynamic version vector maintenance which is used in reconciliation protocol.