A Zero-Trust Approach for Cooperative Vehicular Networks: A Motorway Use Case

Cooperative vehicular networks, integral to intelligent transportation systems, face vulnerabilities from threat vectors that intentionally mislead information to jeopardize safety. Existing methods mainly apply trust levels or message comparison/verification based techniques to address the problem. However, implicit authentication models and considering network nodes as trusted are insufficient in protecting network security against invasive and pertinent attacks. As a solution, Zero-Trust (ZT) networking has the potential to harden the security of vehicular networks. Nevertheless, implementing a ZT in vehicular networks is challenging due to the highly dynamic networking environment, uncertainty in recognizing malicious nodes, and required rapid responses to security breach incidents. This article proposes a robust ZT approach addressing the challenges of implementing ZT in vehicular networks. The approach utilizes a devised collaborative ZT protocol based on subjective logic for trust formation to decide and act against suspected cyber threats efficiently. It also uses verified signatures and autonomous decision-making in accepting/dropping a communication while supporting uncertainty in detecting malicious nodes in a dynamic vehicular environment. The evaluation of the proposed technique demonstrates promising results in malicious node detection accuracy, reduced detection delay, and enhanced goodput. Moreover, the good packet delivery ratio of the proposed approach shows 46% and 14% improvements compared to traditional Public Key Infrastructure (PKI) and another trust-based approach. The findings of this research hold practical directions for enhancing not only vehicular network security but also potentially offering an extension to other networks.