Highly-Secure and Efficient Certificateless AKA for Vehicular Access Networks

This paper proposes a highly secure and efficient certificateless authenticated key agreement (CL-AKA) scheme, which is particularly apt for deployment in vehicular access networks, as it improves not only communication but also computational efficiency in real-world scenarios where multiple vehicles concurrently access the internet via a limited number of base stations. The cornerstone of our CL-AKA scheme stems from an improved certificateless signature (CLS). Specifically, we re-design the key structure of CLS, allowing signers to locally maintain a single public key (instead of two public keys in most state-of-the-art works) as well as two private keys after key generation. With such a novel key structure, the proposed CLS facilitates pairing-free signature generation and verification and realizes efficient batch verification on the verifier’s end. Moreover, a signer only needs to disseminate one public key to verifiers, thus saving communication bandwidth. In addition to the advanced CLS, we develop a CL-AKA scheme that efficiently handles network access requests from multiple vehicles at base stations. To resist physical attacks and achieve highly secure key management, we further integrate the Physical Unclonable Function (PUF) into our scheme. Formal security proofs demonstrate that the proposed CL-AKA scheme is secure against conventional attacks and preserves common security properties such as forward secrecy and session key independence. Finally, we develop a proof-of-concept prototype and conduct extensive experiments to demonstrate the efficiency and practicality of our scheme.