Accountable credential management system for vehicular communication

Social Internet of Vehicles (SIoV) is becoming a reality where private and secure communication is a prerequisite. Various standardization organizations and studies have reached a consensus to use Vehicular Public-key Infrastructure (V-PKI) in order to secure SIoV systems. However, significant security- and trust-related problems remain unsolved. This study presents an Accountable Credential Management System (ACMS) for vehicular communication to solve these problems. ACMS builds on transparency log (Distributed ledger technology) schemes for web PKI but addresses the challenges specific to vehicular communication. ACMS transparently handles certificate-related use cases, namely, certificate provision, registration, validation, and revocation. It also enhances the security of vehicular communication through constant monitoring; hence, assuring that no pseudonym certificate is accepted by vehicles before being logged and witnessed. With an efficient data structure known as the Accumulation Tree (AT), we extend the conventional transparency log to provide a cost-effective and trustworthy authentication process without relying on certificate revocation lists. Time cost and performance analyses show that the proposed approach is feasible and scalable than existing V-PKI schemes. Moreover, using Tamarin Prover, it is verified that our proposed technique provides defense against an active adversary.