Authentication Framework with Enhanced Privacy and Batch Verifiable Message Sharing in VANETs

Vehicular Ad Hoc Networks (VANETs) are the backbone of intelligent transport and enhanced passenger safety, but they face significant challenges related to authentication, security, and privacy. Existing distributed VANET authentication protocols struggle with issues like privacy preservation during vehicle handovers and inefficiency when handling large volumes of verifications. This paper proposes a novel authentication framework designed to address these limitations. First, we introduce zero-knowledge guarantees for Vehicle-to-Infrastructure (V2I) authentication and improve anonymity and unlinkability in authentication by eliminating explicit vehicle handover, thus enhancing privacy. Second, we propose a batch-verifiable Vehicle-to-Vehicle (V2V) message-sharing method utilizing an elliptic curve digital signatures scheme (ECDSA*). Unlike others, we provide a complete computational and efficiency analysis of batch verification in the presence of faulty signatures. A formal security analysis and proven security in the Scyther security verification tool provide the security guarantees of our proposed scheme. A thorough efficiency analysis shows that our scheme can perform at least 5-times more V2I authentication and can batch verify at least 2-times more V2V messages than other related schemes within a time threshold of 300ms.