QoS routing protocol for ad hoc networks with mobile backbones

In this paper, a new QoS routing protocol is proposed for ad hoc network with mobile backbones (MBN). The protocol is based on a proactive intra-group link state updating protocol (ILUP) to avoid the expensive global link state update. It reactively discovers a multiple segmented QoS paths sequentially from the source to the destination. Finding multiple paths can help the routing protocol to account for the imprecision of the link state and to increase the probability to find a feasible path. The protocol can be applied to various QoS routing problems including the minimal delay routing, least cost routing, bandwidth-constrained or the delay-constrained least cost routing. The route search algorithm is modified from the k-shortest path algorithm and the limited path Dijkstra's algorithm (LPDA). Route maintenance strategies for recovery from link breakage and the violation of QoS constraints are also discussed. Simulation results show the efficiency of the proposed protocol.