Mechanism for Detecting and Preventing Security Attacks in VANET

Nowadays communication networks have become very popular. Such types of networks are ad-hoc networks that are categorized into mainly two types, MANET and VANET. MANET is a Mobile ad hoc network that deals with mobile node communication. VANET is a vehicular ad hoc network its main aim is to ensure communication among vehicles while moving to improve safety for drivers by maintaining the autonomous system among vehicles. In VANET each vehicle acts as the intelligent sensor node which is governed by a high mobility system with a dynamic network. These networks are decentralized dynamic networks that are in motion every time and need fast and secure communication among the vehicles. VANET is more vulnerable to attacks. Attacks include various DoS, Warm hole, and Blackhole attacks. Many algorithms have been proposed in the past to investigate various attacks and to provide solutions to prevent these attacks. This document investigates various attacks over VANET and gives an analysis of various algorithms proposed in the past. A study of AODV and its applicability to detect various types of attacks has been presented. In this algorithm, the source node prepares the look-up table to store the route reply packets from all the nodes. It stores the route reply in ascending order. The priority of route replies is taken from the recent sequence numbers. The high sequence number route replies are discarded assuming these routes are obsolete now. This newly submitted algorithm to remove the various attacks has been designed and simulated using Network Simulator 2. It is also being compared with the existing algorithms. It proves the improvement in the detection and prevention of Blackhole attacks. NS2 simulator has been used for simulating this work.