Guaranteed Geocast Routing Protocol for Vehicular Adhoc Networks in Highway Traffic Environment

Geocast routing is one of the most investigated choices for reliable and efficient dissemination of information because of group of vehicles sharing geographic region on the road. Most of geocast routing protocols for intermittently connected Vehicular Adhoc Networks, suffer from low packet delivery, high end-to-end delay and elevated packet loss in intermittently connected networks and low throughput, high hop-to-hop disconnection, larger hop-count in fully connected networks. In this paper, guaranteed geocast routing (GGR) protocol for intermittently connected highway traffic environment has been proposed. GGR utilizes caching and heuristic function for reliable next hop vehicle selection. It also uses FAST (group of neighboring vehicles moving at higher speed than current forwarder) in packet delivery and SLOW (group of neighboring vehicles moving at lower speed than current forwarder) in hop-to-hop failure recovery. One-hop delivery has been guaranteed through acknowledgement. The proposed protocol has been simulated using NS-2 and its performance has been compared with that of adoptive carry-store forward, spray & wait and epidemic routing protocols. Results reveal that the performance of GGR is better in terms of number of routing matrices considered for both intermittently and fully connected networks.