Vehicular Ad-hoc Networks (VANET) are a special kind of Mobile Ad-hoc network (MANET), in which vehicles on the road forms the nodes of the networks. Now a days, VANETs find several applications as an Intelligent Transportation System. Dynamic network architectures and node movement characteristics differentiates VANETs from other kinds of ad hoc networks.Since VANETs have a dynamic network topology, routing in VANETs are complicated. Ad-hoc On-Demand Distance Vector (AODV) routing protocol is the most commonly used topology based routing protocol for VANET.