Research On Routing Protocol Based On Road Of Time Delay And Number Of Vehicles In VANET

There are many problems in the traffic environment, like traffic congestion, trafficresource utilization is low, frequent traffic accidents and other traffic problems, the traditionalapproach in solving these problems have emerged bottleneck. In order to solve the trafficproblems, Intelligent Traffic System of advanced computer technology and communicationtechnology have emerged. VANET provides support for communication of inter-vehicle, wecan develop convenient and practical software based on the VANET for people of travelling toprovide more convenient services, as well as safety.VANET compared with Ad Hoc network has its own characteristics, such as nodesmoving with high speed, link duration is short, unstable link quality, topology changesfrequently and so on. This makes designed routing algorithms for MANET is not suitableusing in VANET. The routing protocols based on geographic location have better performancein VANET, the representative of the class of routing protocols is GPSR, GPSR lack of overallawareness of the global information of road, so it is easy to fall into local optimizationproblem, and then you need to enter surrounding forwarding mode or carry-forward mode,which will cause data forwarding with high packet loss rate and time delay issue, so it shouldbe avoided GPSR in this issue..In order to solve the problems in GPSR, we need to have a global cognitive about thetopology of road, as a basis for determining the transmitted path of the packet. We abstracttopology of road as a graph, the road be seen as edge of graph and the junction be seen asnode of graph. We put a vehicle that is not moving at each intersection. In urban scene, theroad over a period of time can provide a stable communicated capability, we assess the timedelay of each road to transport packet and use this value as the weights of edges in the graph,take algorithm of Dijkstra to calculate a path to destination. The nodes in VANET by sendingdetecting packet to calculate the time delay of each road, the way of detecting packet choosenext junction as same as Depth-First Search algorithm of graph, we can get the time delaydata of each road and broadcast the information. If the node in VANET found the time delaydata losing its timeliness, it will send detecting packet to solve the problem. We design three modes for the routing algorithm: the mode for straight road, the mode for junction andrecovery mode. The nodes in VANET need to consider not only the position of neighbornodes, but also to consider the direction of neighbor nodes, in order to reduce the packet lossrate, we design a method to predict neighbor node’s location. When a node that put on theintersection received a packet, the node will select a node on the desired path for dataforwarding. Once the data transfer process does not match with the desired path, the nodeholding the data at this time to recalculate a path for transferring data. In order to improve thesuccess rate of packet delivery, calculating the number of vehicles on the rode while detectingpacket calculate time delay data about the road, and then according to the number of vehicleson the road, using the proposed method to select a path with higher success rate for datadelivery. In the process of data delivery, we can calculate the time delay data and the numberof vehicles, which can improve the accuracy of the associated weights.We use NS2, SUMO and MOVE to verify the proposed routing protocol, it comparedwith GPSR protocol has better performance in end to end delay and success rate of datadelivery. Through the analysis of experimental data, we reach intended purpose.