A Study on Efficient Anonymous Authentication Scheme in Vehicular Ad - hoc Networks

Vehicular Ad-hoc Networks (VANETs) are one of typical application of wireless communication technology, which provide communications among nearby vehicles and between vehicles and roadside units (RSUs) connected the infrastructure. VANETs provide a perfect way to collect dynamic traffic information and sense various physical conditions related to traffic distribution with very low cost and high accuracy, which have a great potential to revolutionize driving environment, and will undoubtedly play an important role in the future transportation system. However, it is clear that security and privacy enhancing mechanisms are necessary, which are in fact a prerequisite for deployment. This has been recently well understood in academia, the industry, and among authorities. And a large number of agreed efforts have been undertaken to design security architectures for VANET systems. Extensive research efforts have been made by both industry and academia to make VANETs secure. In this thesis, we proposed a novel anonymous authentication scheme in VANETs. Our proposed scheme guarantees authentication, anonymity, unlinkability, and traceability simultaneously. The unlinkability which enables privacy preservation and the traceability which enables conditional tracking are contradictory. We utilize the traceable ring signature scheme with the k-times anonymous authentication scheme to address the contradictory between the unlinkability and the traceability. Our scheme also uses elliptic curve cryptosystem to achieve storage, computation, and communication efficiency. Compared with existing works, we claim that our scheme has better performance in terms of storage, computation, and communication overhead. In addition, our scheme has three advantages compared with other previous works. First, our scheme doesn’t have revocation list update process in authentication process. Second, our scheme always provides unlinkability although multiple RSUs are compromised. Finally, our scheme requires only one authentication process for mutual authentication when the vehicle communicates with the same RSU, because our scheme has key agreement functionality that makes secure channel to communicate. These advantages make our scheme efficient in large-scale and busy networks like VANETs.