Infrastructure aided privacy preserving-authentication in VANETs

Abstract

The paper presents a privacy preserving authentication protocol for vehicles in a VANET. The authentication process involves authentication of the vehicle and the corresponding RSU by a fixed infrastructure (CTA). Every RSU has a public key infrastructure and continuously broadcasts public key. The vehicle encrypts its identity, RSU Id and timestamp using its symmetric key. The encrypted bits along with the pseudonym of vehicle and timestamp are again encrypted by the public key of RSU and send to the RSU. RSU forwards the encrypted part to the CTA. CTA sends its verification to the RSU. The verification of the vehicle is encrypted by the vehicle symmetric key and sends along with authentication of the vehicle to the RSU. The encrypted portion is forwarded to the vehicle which confirms the authentication of the RSU after decryption. The CTA also sends a temporary short certificate to the vehicle for vehicle to vehicle communication. The whole process needs only one request and reply between different entities. Simulation results indicate the time taken (~ 223 ms) for the whole process is small and constitutes only a small portion of the stay time of a vehicle within an RSU region. © 2010 Springer-Verlag Berlin Heidelberg.