Abstract: To solve the efficiency problem of batch anonymous authentication for vehicular Ad-hoc networks (VANET), an improved scheme is proposed by using bilinear pairing on elliptic curves. The signature is jointly generated by roadside unit(RSU) node and vehicle, thus reducing the burden of VANET certification center and improving the authentication efficiency, and making it more difficult for attacker to extract the key. Furthermore, under random oracle model (ROM) security proof is provided. Analyses show that the proposed scheme can defend against many kinds of security problems, such as anonymity, man-in-the-middle (MITM) attack, collusion attack, unforgeability, forward security and backward security etc., while the computational overheads are significantly reduced and the authentication efficiency is effectively improved. Therefore, the scheme has great theoretical significance and application value under computational capability constrained internet of things (IoT) environments.

Key words: bilinear pairing, anonymous authentication, privacy protection, vehicular Ad-hoc networks, random oracle model