A Routing Protocol Improvement On Vehicular Ad Hoc Networks In City Scenarios

Vehicular Ad Hoc Networks is a special kind of mobile ad hoc networkswhich consists of wireless communication devices on car. Its applied value ismainly reflected in two aspects: on the one hand, it can achieve a variety ofintelligent transport applications, including traffic detection, traffic management,vehicle navigation and emergency response; on the other hand, it can also meetthe user’s need of car communication and entertainment. In recent years, VANEThas become the focus of Ad Hoc Networks research. Due to the high dynamicnature of network topology owned by VANET, routing protocols of traditional adhoc network can’t work well in VANET, with data forwarding becoming the mainproblem. The paper first made a general introduction of VANET, including adetailed analysis of its characteristics and the corresponding influence on routingprotocols. Then the paper summarized the important VANET routing protocols ofthese years, studied on the core routing mechanism of the various routingprotocols as well as its advantages and disadvantages, and analyzed the influenceof various technologies on the performance of the routing protocol. Next, astimulation method of VANET was introduced to lay the foundation for theeffectuation of the VANET simulation system.According to the characteristics of VANET and vehicle motion model inCity Scenarios, the paper finally provided a VANET routing protocol-SSRprotocol based on road state information and vehicle speed information. In thisnew protocol, during the data forwarding, the node not only uses the locationinformation but also takes advantage of road state information or the speedinformation of nodes around according to the its own type, which makes a greatimprovement.The paper made a detailed introduction of the new protocol, including thecore idea and routing strategy and gave out the overall design as well as specificrealization method. Besides, because the simulation can use the realistic vehiclemotion model to better evaluate the performance of the protocol and furtherreduce the unnecessary expenses, the paper employed VanetMobisim to simulatevehicle motion model, effectuated the new protocol in NS-2, and finally verified through experiment that SSR protocol has better performance compared withtraditional VANET routing protocol.