An Efficient Path Pruning Algorithm for Geographical Routing in Wireless Networks

Geographical routing is powerful for its ability to discover a path to the destination without the help of global states. However, stateless geographical routing usually involves a large number of hops when detouring around voids of the network. In this paper, we propose an efficient path pruning (PP) strategy to reduce the excessive number of hops caused by the detouring mode of geographical routing protocols. The PP algorithm finds routing shortcuts by exploiting the channel listening capability of wireless nodes and is able to reduce a large number of hops with the help of a little state information passively maintained by a subset of nodes on the route. We also discuss algorithm properties and implementation considerations and provide simulation results demonstrating the effectiveness of the proposed algorithm in shortening the routing path and improving delivery rate when it is applied to existing geographical routing protocols.