A REVIEW ON VANET, TYPES, CHARACTERISTICS AND VARIOUS APPROACHES

A Vehicular Ad - hoc Network (VANET) is a collection of wireless vehicle nodes forming a temporary network without using any centralized Road Side Unit (RSU). VANET protocols have to face high challenges due to dynamically changing topologies and symmetric links of networks. A suitable and effective routing mechanism helps to extend the successful deployment of vehicular ad - hoc networks. An attempt has been made to compare the performance of two On - demand reactive routing protocols namely AODV and DSR which works on gateway discovery algorithms and a geographical routing protocol namely GPSR which works on an algorithm constantly geographical based updates network topology information available to all nodes in VANETs for different scenarios. Comparison is mad e on the basis of different metrics like throughput, packet loss, packet delivery ratio and end - to - end delay using SUMO and NS2 simulator. In this paper we have taken different types of scenarios for simulation and then analyzed the performance results