Angle-Aware Greedy Forwarding Algorithm for Vehicular Ad Hoc Networks

Greedy Perimeter Stateless Routing (GPSR) gives the good forwarding nodes for Mobile Ad Hoc Networks (MANET) but does not provide the right directional forwarding nodes in Vehicular Ad Hoc Network (VANET). This is the fact that MANET uses the nodes without limitations in moving but VANET uses fixed infrastructure in mobility such as roads with lanes. The key of original greedy forwarding is choosing the forwarding node with the shortest distance between the source and the destination. It does not consider the direction of the forwarding nodes, which possibly cause the selected forwarding node going opposite direction from the destination. This paper thus tries to improve the greedy forwarding method of Greedy Perimeter Stateless Routing (GPSR) by taking into considerations in both the distance and the direction. Moreover it shows the mystery of angle that gives the right direction. The optimized GPSR (OGPSR) using improved greedy forwarding provides the better throughput, average end-to-end delay and routing overheads than the original GPSR.