A Realistic Distributed Conditional Privacy Preserving Authentication Scheme for Vehicular Ad Hoc Network

Nowadays, the research of tradeoff between reliance on the tamper-proof device (TPD) and storage space in authentication scheme has become an interesting topic for vehicular ad hoc networks (VANETs). Most recently, to minimize the dependencies of TPDs and reduce the storage space, Zhang et al. proposed a conditional privacy-preserving authentication scheme based on a multiple trusted authority one-time identity-based aggregate signature technique. It is more practical than other related schemes due to not depending on ideal TPDs. However, Zhang et al.'s scheme requires a fully trusted third party to participate in the authentication and member secrets generate phase, which may suffer from security bottleneck. To overcome this weakness, in this paper, we construct a realistic distributed conditional privacy-preserving authentication scheme for VANETs using identity-based cryptography and short lifetime region-based certificate. Comparing with Zhang et al.'s scheme, the proposed scheme has more security features but does not reduce computation and communication efficiency. The security analysis shows that our scheme is provably secure in the random oracle model.