Direction-based Greedy Forwarding in Mobile Wireless Sensor Networks

Geographical routing in mobile wireless sensor networks has attracted big attention in recent years by introducing new challenges. When a node has a packet to forward, it selects the closest available neighbor to the sink as the next forwarder regarding only the location parameter. However, this routing strategy does not consider the topology changes caused by the mobility of nodes, which may degrade performance or cause failures. To overcome this problem, we propose an efficient greedy forwarding mechanism based on a new decision metric that considers the distance to the sink, the moving direction and the moving speed of the forwarding candidate neighbors of a sender node. The moving direction depends on both distance and angle of a neighbor according to the sink between two successive location beacons. Associated with the well-known GPSR routing protocol, our proposal achieved good performance in terms of packet delivery ratio, average path length, control packet overhead and energy consumption. Keywords—Mobile sensor networks; geographical routing; node mobility; greedy forwarding.