EPAF: An Efficient Pseudonymous-Based Inter-vehicle Authentication Framework for VANET

Road users are now able to retrieve safety information, computing task results and subscribing content through various vehicular ad hoc network (VANET) services. Most commonly used services are safety beacon, cloud computation, and content subscription. Road users concern more about data security than ever. Privacy preserving authentication (PPA) is one main mechanism to secure inter-vehicle messages. However, for historical reasons, PPA for three services are different and therefore hard to be unified and not lightweight enough. To improve the flexibility and efficiency of PPA for various VANET services, it is necessary to securely authenticate messages preserving privacy for individual service, but also to unify PPA processes of various services in one vehicle. Here we propose an Efficient Pseudonymous-based Inter-Vehicle Authentication Framework for various VANET services. Our novel framework employs three methods. Method No. 1 consists of a decentralized certificate authority (CA), which allows vehicles to communicate only if vehicles registering themselves. Method No. 2 adopts a three-stage mutual authenticating process, which adapts to different communicating models in various services. Method No. 3 we design a universal basic module that requires only lightweight hashing and MAC operations to accomplish the signing and verifying processes. To analyze the security performance of our EPAF, we use automated tool under symbolic approach. Our results strongly suggest that EPAF is secure, robust and adaptable in vehicular safety, as well as in content and cloud computation services. To analyze the performance of EPAF, we calculate benchmarks and simulate the network. Our results strongly suggest that EPAF reduces computation cost by 370–3500 times, decreases communication overhead by 45.98%–75.53% and CA need not to manage CRL compared with classical schemes. In conclusion our framework provides insights into how data privacy can be simultaneously protected using our EPAF, while also improving communication and computing speed even in high traffic density.