Moving Direction Based Greedy routing algorithm for VANET

Packets transmission over VANET is intermittent due to rapid change of network topology. This comes from both high mobility of mobile nodes and limitation of roads. Intermittent transmission causes inefficient packet delivery. Those routing protocols applicable to MANET might not be suitable for VANET. In this paper, we propose a Moving Direction Based Greedy (MDBG) routing algorithm for VANET that is used to enhance routing decision in packet delivery. MDBG algorithm is based on the geographical information collected by GPS. In MDBG, the source vehicle uses "hello message", Destination REQuest (DREQ) and Destination REPly (DREP) messages together with its own moving direction information to establish a stable routing path by selecting appropriate neighbor vehicles. AODV algorithm has been proved to have good performance when both the source vehicle and target vehicle have the same moving direction. MDBG algorithm is proposed to leverage the problem while source vehicle and target vehicle move far apart in opposite directions. Simulation results show that MDBG outperforms both AODV and DSR in packet arrival rate, throughput and average end-to-end delay.