中文摘要：

针对城市车载网络中因自私节点及恶意节点存在造成的消息成功传输率低下的问题,提出一种消息安全传输机制。在城市环境下,用TPM芯片标识车辆。综合节点间成功转发消息及接触次数,得出好感值,并融入对车辆节点的移动方向及速度的考虑,得出节点的效用值,以此衡量节点间的信任程度,找出适当的下一跳车辆节点,保证消息的安全传输。同时,利用两次握手协议来确保节点间的连通性,减少网络中断问题,增加消息的成功传输率。此外,引入图论的概念,构造城市车载网络中的无向加权图,利用Floyd算法求出消息的最短传输路径,减少网络开销。仿真结果表明,该种机制下的消息成功传输率达到90%以上,且网络开销性能值低于200。

英文摘要：

For the problems of the low forward successfully rate of news which because of selfish nodes and malicious nodes in the city VANETs, this paper proposed a message security transport mechanism. In urban environments, TPM chip as the unique identification of the vehicles nodes. Comprehensive the successful forwarding messages and contact number between nodes, the friendly values could be got. Then in order to determine the appropriate the next-hop message forwarding nodes, the mechanism was calculate the utility value of nodes through take the moving direction and speed of the nodes into consideration based on friendly values. At the same time, this mechanism used the two-handshake protocol before forwarded messages to ensure the connectivity between nodes. Besides, in the field of promote the transmit speed, the mechanism made full use of Floyd algorithm to find the shortest path to transmit to news by built a non-direction graph in city. After this, it can be ensured that message trans-mission quickly and reduce the network overhead. Simulation results show that the successful forwarding rate of the news is over 90%and network overhead is below 200 under the mechanism.