The Research On Algorithm Of Delay Tolerant Data Delivery In Vehicular Ad Hoc Network

With the development of wireless technology and automobile industry in recent years, the vehicular ad hoc network(VANET) becomes the key of realizing the intelligent transportation system and improving safety and efficiency of traffic. The automobile industry, academia and government have put much joint efforts to research it. Data delivery is an import part of the VANET to provide data transmission service.However the VANET is a special delay tolerant network, it faces such challenge as a rapid changing of network topology brought by the high moving speed, intermittent communication and the interference of the buildings. There is no reliable path between source node and destination node, and the end-to-end communication can not be guaranteed. So the routing protocol to provide service of data delivery is a very important research issue, which ensures the effective and reliable communication.The thesis introduces the VANET and the classical routing protocols. The thesis proposes the parked vehicle assisted and mobility-aware adaptive routing algorithm(PVMAR) based on the fact that there are many parking vehicles in urban and vehicles are moving with a certain regularity. The algorithm mainly consists of three parts: First,we build a stable backbone network on the top of the highly dynamic VANET; Second,we study the regularity of vehicles and build mobility model for it; Third, we use the mobility model to forecast the position of target vehicle and delivery the message to target position through the backbone network, and the message is delivered when the target vehicle passes through the position. In view of the problems of selfish nodes in the VANET, the thesis proposes the social contribution-based routing algorithm(SCR).The algorithm defines the delivery probability to measure the probability of message delivered, and defines the contribution of node to measure the contribution of forwarding messages. When the node carrying the message choose the relay node to delivery the message, it prefers to choose the node with high delivery probability and low contribution. At last, we use the ONE to simulate the two algorithms proposed,the simulation results show that they perform better than other delay tolerant algorithms in the aspect of the message delivery ratio, network overhead ratio and average latency.