Research On Secure Mechanism For Position-based Routing In VANETs

VANETs have a great commercial potential. They do much help in Intelligent Transportation System (ITS) field. But some security problems have not been solved perfectly yet. A scheme to improve security performance proposed in this paper make a great sence in protecting the routing protocol. It mainly aims at defending the attacks like black hole attack, worm-hole attack which ruins the routing validation; and it also can protect data from being tempered.Basic security protocol theory is researched in this paper. Symmetric keys management and asymmetric keys management scheme is introduced in the paper. And two kinds of asymmetric keys management scheme are analyzed in detail. One is ID-based key management scheme, the other one is ECC based combined public key scheme. We design a position-based protocol. An evaluation to neighbor node mechanism is applied in the protocol. Also this protocol employs digital signature to guarantee the identity authentication. The security performance is analyzed in theory. For testing the network performance and security performance of the protocol, we implement the protocol based on GPSR module in NS2system. MOVE tool is used to generate the real traffic model script. And NS2apply this script to do simulation and finally generate the simulation data. Three situations, namely the normal network situation, the network with a packet drop malicious node, the network with a data tampered malicious node, are simulated upon this protocol. We adjust and optimize the protocol upon the network simulation data of the three situations. The evaluation scheme in the protocol is the mainly achievement of our paper and experiments. The security protocol proposed in this paper defends the drop packets attack effectively, protects the data link from being cut off by malicious nodes. And provide the protocol the ability to choose reliable routing path.