A Comprehensive Survey of Routing Strategies for Vehicular Ad-Hoc Networks

Vehicular Ad Hoc Networks is an emerging new technology which incorporates ad hoc network, wireless LAN (WLAN) and cellular technology, which has been taken huge attention in the recent years to enhance active and preventive traffic safety on the road as well as travel comfort. In Vehicular Ad Hoc Network, vehicles acts as nodes, this can be treated equally for data delivery.VANET provides wireless communication among vehicles (V2V) and vehicle to roadside infrastructure (V2I). In VANETs nodes are highly mobile, so the network topology changes frequently. Due to dynamic topology, network partitioning and high vehicular speed characteristics make it difficult to design an efficient routing protocol for propagating data, Therefore design of an efficient routing protocol has taken significant attention and that is the reason it is extremely necessary to identify pros and cons of routing protocols which may be used for additional enhancement or development of the new routing protocol. In this paper we provide a brief review of the main 6 types of routing strategy for VANET along with major classifications, open issues and challenges. The protocols have been compared in a tabulated form based upon their essential characteristics.