Blockchain-Based Enhancement to V2X Security

Abstract

Current C-ITS security relies on the Public Key Infrastructure (PKI) and Certificate Authority (CA) model called VPKI. This involves a complex hierarchy of Certificate Enrolment Authorities (EAs) and Authorization Authorities (AAs), with the Intelligent Transportation System ITS station (Vehicle OBU or RSU) issuing long-term identifiers and short-term Authorization Tickets (ATs). However, this centralized PKI/CA system faces difficulties in cross-border and cross-organizational scenarios and incurs high processing costs for message verification. This research introduces the Distributed Public Key (DPK) Ethereum Blockchain platform for Vehicle-to-Everything (V2X) communication, designed to store C-ITS long-term certificates and AA public keys. It tackles scalability challenges and enhances cross-domain interoperability, reducing V2V communication latency and simplifying certificate management. Smart contracts in DPK facilitate real-time storage and access to vehicle certificates and AA public keys, thereby easing authentication and enhancing interoperability across various domains. Initial testing indicates a significant reduction in V2V message verification time and the successful establishment of secure, end-to-end communication sessions among C-ITS entities. These results highlight the approach’s potential as a scalable and effective security solution for V2X networks. The system was evaluated through simulation on Ethereum 2.0 and the Sepolia test network. Since this Ethereum implementation is a proof of concept, a private blockchain is recommended for real-world deployment applications.