Enhanced Caching for Geocast Routing in Vehicular Ad Hoc Network

Abstract

In vehicular ad hoc network (VANET), the major challenge for routing protocol is to find a route from the sender to the destination without any preconfigured information under constantly varying link circumstances. Topology-based routing is strictly avoided because of frequent changes in the topology. The approach of position-based routing relies only on geographical position information to deal with the problem of dynamic topology changes. Also, in most of the intelligent transport system (ITS) applications such as collision warning, advertising, alerts message, information needs to be disseminated in a predefined geographical region. That is why, position-based geocast routing is a suitable candidate for VANETs since position information is already available from navigation systems. In this paper, we have proposed a novel geocast routing protocol named “Enhanced Caching for Geocast routing (ECGR)” that takes the advantage of “Geocast in Vehicular Environments: Caching and Transmission Range Control for Improved Efficiency (CTRC)” and can be used in various ITS applications. The main contribution of our work is to introduce a novel coverage determination algorithm. This algorithm improves the caching methodology of CTRC and almost eliminates the packet loss due to high-speed movement of vehicles. Our new protocol also improves the throughput of the system by eliminating the range-forwarding approach of CTRC and using full radio transmission range of the vehicles to forward packets.