An improved vehicular ad hoc routing protocol for city environments

The fundamental component for the success of VANET (Vehicular Ad hoe NETworks) applications is routing since it must efficiently handle rapid topology changes and a fragmented network. Current MANET (Mobile Ad hoc NETworks) routing protocols fail to fully address these specific needs especially in a city environments (nodes distribution, constrained but high mobility patterns, signal transmissions blocked by obstacles, etc.). In our current work, we propose an inter-vehicle ad-hoe routing protocol called GyTAR (improved Greedy Traffic Aware Routing protocol) suitable for city environments. GyTAR consists of two modules: (i) dynamic selection of the junctions through which a packet must pass to reach its destination, and (ii) an improved greedy strategy used to forward packets between two junctions. In this paper, we give detailed description of our approach and present its added value compared to other existing vehicular routing protocols. Simulation results show significant performance improvement in terms of packet delivery ratio, end-to-end delay, and routing overhead.