Abstract: To solve the problem of security and efficiency of anonymous authentication in the vehicle Ad-hoc network（VANET）, a conditional privacy protection authentication scheme for vehicular networks is proposed based on bilinear pairings. In this scheme, the tamper-proof device in the roadside unit (RSU) is used to complete the message signature and authentication process together with the vehicle, which makes it more secure to communicate between RSU and trusted authority (TA) and faster to update system parameters and revoke the vehicle. And this is also cheaper than installing tamper-proof devices in each vehicle unit. Moreover, the scheme provide provable security proof under random oracle model (ROM), which shows that the proposed scheme can meet the security requirements such as conditional privacy, unforgeability, traceability etc. And the results of simulation experiment demonstrate that this scheme not only of achieves high efficiency, but also has low message loss rate.

Key words: VANET, anonymous authentication, bilinear pairings, conditional privacy protection