On the reliability and utilization enhancement for local repair in on demand ad hoc networks

The ad hoc on-demand distance vector (AODV) routing protocol is proposed for achieving dynamic, self-organizing and on-demand multihop routing among mobile nodes in mobile ad hoc networks (MANETs). In AODV, wireless links may be lost occasionally due to the nodes on the routing path that are unreachable. For solving the problem, the AODV protocol provides a local repair mechanism that tries to find an alternative route to destination by broadcasting the RREQ message from the upstream node of the broken. Although the local repair mechanism works with a specified TTL to limit the repair range of RREQ, large number of the broadcast RREQ messages result in extensive control messages and obvious power consumption for transmitting these broadcast messages. Therefore, in this paper we propose an unicast-type multihop local repair protocol to recovery the lost links efficiently while increasing network reliability, increasing utilization, minimizing the number of control messages and shortening the repair delay. Meanwhile, the optimal number of hops of neighbor table is also analyzed. Numerical results indicate that the proposed multihop local repair approach outperforms other repair approaches in fixed successful rate, control message overhead and network utilization