ELCPH: An Efficient Lightweight Conditional Privacy-Preserving Authentication Scheme Based on Hash Function and Local Group Secrete Key for VANET

Vehicular ad-hoc networks (VANETs) have got a wide range of attention to improve traffic systems and smart cities. Security and privacy are critical issues and need to be addressed for effective VANET systems. In this paper, we propose an efficient conditional privacy-Preserving authentication scheme based on a group secret key. Many VANETs schemes have utilized a group signature to realize the identity-less authentication, but the existing schemes suffering from long and high computational procedures, especially in the Certificate Revocation List (CRL) verification process, and group management complexity issues. As a result, they cannot satisfy the VANETs efficiency requirements. On another hand, many pseudonym-ID based VANETs schemes utilized a system key signature, but those schemes suffering from communication overhead increasing which could be caused by the increasing of the revocation list, in addition to that, and any damage in the key will cause damage for the entire system. In our scheme, we use a permanent vehicle pseudonym-ID and temporary group secret key that offers a lightweight verification and authentication process for a secure and efficient VANET system.