Abstract
In this work, it reviewed the recent authentication scheme based on certificateless aggregate signature (CLAS) in vehicular ad hoc network (VANET). The previously proposed scheme solved a few of the security problems in VANETs, but it cannβt resist forgery attacks. Besides, the computation and communication cost is not sufficiently low that would affect the efficient delivery of emergency traffic messages. In this paper, we propose a new efficient cerificateless fully aggregate signature scheme for VANETs. The proposed scheme used the general one-way hash function operations instead of the expensive map-to-point hash functions. It inherits the characteristics of CLAS by aggregating various message signatures from different vehicles into a single signature, thus reducing the computation and communication overhead of the scheme. A lightweight conditional traceability method is designed to enable the traffic management department to reveal the real identity of malicious vehicles. Based on elliptic curve discrete logarithm (ECDL) problem, it proved that the proposed scheme is existential unforgeability under the adaptive chosen-message attack and satisfies security goals. Performance analysis shows that our scheme is more efficient than similar schemes in terms of computation and communication overhead. It will reduce at least 24.3% in computation cost than compared schemes.