A novel blockchain-based anonymous roaming authentication scheme for VANET

With the widespread application of vehicular ad-hoc networks, ensuring secure and seamless cross-regional roaming for mobile users and obtaining corresponding services has become a focal point. However, designing an efficient and secure roaming authentication protocol is challenging due to the confidentiality and privacy issues that data transmission during the roaming authentication process may cause and the limited computational capabilities of mobile devices. Researchers have proposed many security-oriented schemes to address this thorny challenge. However, many state-of-the-art schemes need help meeting various security requirements and facing privacy leakage and single points of failure. Recently, Xue et al. proposed a distributed authentication scheme for roaming services in mobile vehicular networks based on smart contracts. Regrettably, it is noted that their scheme is vulnerable to ephemeral key leakage attacks. Further, we present a blockchain-based anonymous roaming authentication scheme called BARA, which changes how session keys are generated and significantly reduces on-chain storage costs using probabilistic data structure techniques. We utilize Scyther and Burrows–Abadi–Needham (BAN) logic to prove the security of BARA and compare it with similar protocols in terms of computation, communication, and revocation check. The analysis results demonstrate that BARA achieves a good balance between security performance and execution efficiency.