Anonymous Identity Authentication Scheme for VANETs

The application of vehicular ad hoc networks (VANETs) is of great significance to traffic optimization and traffic safety. The network security of VANETs becomes the key to restrict the development of VANETs. In this paper, we propose an anonymous authentication scheme for VANETs, in which we avoid using certificates in the authentication process between the RSU and the vehicle. This identity-based authentication scheme solves the problem of certificate storage and management in the authentication protocols based on the public key infrastructure(PKI). In our scheme, the system key isn't stored in the roadside unit (RSU) or the tamperproof device (TPD) of the vehicle like some other schemes. When the RSU communicates with the vehicles, the local key generated by the RSU is used to sign the transmitted message, so that even if the local key of the RSU has been leaked, the security of the entire system will not be affected. And the RSU can update the local key to improve the security of the communication. The scheme uses timestamps in authentication, key agreement and message signing, which effectively avoids replaying attacks. The analysis shows that the proposed scheme can satisfy the security and privacy requirements of VANETs. The message authentication computation costs and communication overhead are improved.