In the near future, vehicular ad hoc networks (VANETs) are expected to be more widely deployed, where vehicles would be equipped with on-board... Show moreIn the near future, vehicular ad hoc networks (VANETs) are expected to be more widely deployed, where vehicles would be equipped with on-board devices that permit wireless networking between vehicles on the road, and between vehicles and in- frastructure. To ensure security and privacy, digital signature and veri cation schemes have been extenstively developed. The group signature implemented in VANETs causes large computation overhead, While the On Board Units installed on vehicles have limited CPU computing capacity. To address this issue, a practical cooperative message authentication protocol (CMAP) is designed and simulated in this work. In the protocol, vehicles share their veri cation results with each other in a cooperative way so that each vehicle just needs to verify a small number of messages. Compared with other work considering 1-D highway road scenario, 2-D city road scenario is built with the tra c simulator VanetMobiSim. Our CMAP simulation is based on the basic Periodic BroadCast (PBC) platform available in newer versions of ns-2 system. The protocol design and all detailed procedures of CMAP algorithms are implemented in the network simulator ns-2 with C++ programming. The simulation also evaluates the performance of CMAP with metrics including missed detection ratio, CPU load, under conditions of di erent vehicle densities and di erent numbers of veri ers. The performance of our CMAP with n-nearest veri er selction method is compared with previously reported probabilistic veri cation method, and shows the advantage. M.S. in Electrical Engineering, July 2012 Show less
