Global clustering based geo cache for Vehicular Ad hoc Networks

Several medium access control protocols have been proposed in the recent past for vehicles for accessing radio channels and for distributing timely active safety messages for inter-vehicle communication in Vehicular Ad hoc Networks (VANETs). As contention period is high in Medium Access Control (MAC) for channel access, MAC is unable to distribute timely safety messages. To reduce the contention period, Region based Clustering Mechanism (RCM) is applied with MAC protocols. RCM caters to the reduction of contention because the number of vehicles for each cluster is limited. In addition, it resolves the competition among vehicles to access radio channels for inter-vehicle communication. Ad Hoc On-Demand Distance Vector (AODV) routing protocol is used for providing shortest path between source and destination which increases the amount of packet reception and cluster formation. Geo cache is included in VANET in order to retain directory that includes information about nodes that have left a particular cluster through neighboring nodes.