A Novel Cloud-Assisted Authentication Key Agreement Protocol for VANET

Vehicular Ad hoc Networks (VANET) serve as an emerging technology to provides great promise for building intelligent transportation systems with convenient, enriched, and smart transportation services. Furthermore, VANET provides an intelligent platform that enables vehicles and infrastructures to share relevant information through communication, facilitating vehicle predictions of road conditions and reducing traffic accidents. Therefore, VANET faces intricacies and vulnerabilities to various security threats. Generally, to further achieve secure communication, the authentication key agreement (AKA) protocol is a crucial technology in VANET. However, the existing AKA protocols for Vehicle-to-Vehicle (V2V) communication still have some challenges. Firstly, most protocols can only achieve one-to-one identity authentication, and can not authenticate with multiple users at once, which is inefficient. Secondly, some schemes have one-to-many authentication functions but also have a linearly increasing storage cost, and their complex operations pose an expensive computational burden on resource-constrained devices. To further address these shortcomings, we propose a novel AKA protocol that utilizes the vehicle's attributes as identity, allowing for multiple identity authentication. In the extended Canetti-Krawczyk (eCK) security model, our protocol satisfies the unforgeability of messages and indistinguishability of session keys based on the hardness of the complexity assumptions. Furthermore, we conducted simulations of our protocol using ProVerif, a formal proof tool, which confirms that our protocol satisfies the security properties. To evaluate the performance of our proposal, we analyzed it using JPBC, a cryptographic library based on the Java language, as well as Veins (Omnet++ and Sumo), and the results indicate that our proposal outperforms other schemes and is suitable for deployment in high-traffic, high-density, and resource-constrained VANET scenarios.