Study On Location Based Secure Routing Protocol In Vehicular Ad Hoc Networks

Vehicular Ad Hoc Networks(VANET) is a kind of Mobile Ad Hoc Networks(MANET), which provides the communications between the vehicle and the vehicle, or the vehicle and the Road Side Unit(RSU). Since VANET has a great potential in improving road safety, improving traffic efficiency and providing conventient for drivers and passengers, it has become one of the wider research fields. VANET is a special application of MANET, hence it suffers from the various known and unknown attacks of MANET, such as discarding information, replaying, denial of service attack, etc. At the same time, there are some special attacks against VANET, such as position attack, hiding vehicles, privacy protection, tunnel attack, and so on. Therefore, the main work of this thesis is to design a secure routing protocol in VANET which is able to achieve privacy and security.The security of the GPSR protocol(Greedy Perimeter Stateless Routing) is analyzed and a modified GPRS protocol based on Roadside Unit’s prevention and detection is presented in this paper. The modified protocol improves the security of GPSR protocol by adding message authentication, privacy protection, location detection, forgery attack, and other functions in GPSR protocol. The new protocol uses GPS module to obtain its own position, speed, direction, timestamp and other information and this information is added into the original beacon messages. In addition, The Roadside Units carry out identity authentication, replay attack detection and location attack detection, information tampering detection, sybil attack detection, etc. At the same time, the alarms are divided into RSU warning and vehicle alarm. Roadside unit collected beacons and determined whether an RSU warning is sent or not. In the vehicle alarm, alarm time, alarm location and the position of the vehicle were added to the original alarm message. The Roadside Unit verified the vehicle alarm by vehicle characteristics, which is able to solve the problems of forgery attack and hidden vehicles. In order to prevent information eavesdropping in forwarding process, the identity of the source node, the location and communication message are encrypted.NS2 simulation platform is used to simulate the improved protocol. The improved protocol is compared with the GPSR in average delay, packet delivery ratio. The simulation results show that the delay of the improved protocol increases slightly, and delivery rate increases significantly when there are some malicious nodes, The security performance is good.