Three load metrics for routing in ad hoc networks

Most existing routing protocols for mobile ad hoc networks are designed to search for the shortest path with minimum hop counts. However, the shortest routes do not always provide the best performance, especially when there are congested nodes along these routes. We investigate a load-aware routing protocol using three load metrics for route selection, which include MAC layer channel contention information, the number of packets in the interface queue, and the traditional hop count. Among these metrics, MAC layer contention information provides an accurate estimation of neighbor node activities, and queue length provides a measure of traffic load at the mobile node itself. Combined with the number of hops, this load-aware routing protocol can effectively balance the traffic and improve throughput within the ad hoc network. The impact of these three load metrics on the routing performance are studied, and simulations are conducted to validate our conclusions.