Zero-Knowledge Proof for Enabling Privacy Preserving Electronic Toll Collection with Vehicle-to-Everything Communications

ETC systems today use technology that can be exploited to track toll users. This work develops a GPS-free toll collection that uses a zero-knowledge proof to verify V2X On-board units (OBU) in a way that prioritizes security and privacy while accommodating resource limitations of the embedded technology. Our privacy preserving ETC protocol consists of three parts: a mutual authentication handshake, a zero-knowledge proof challenge, and a verification for toll-payment processing. Bench analysis evaluates embedded systems' limitations of algorithmic operations, and field tests of challenges are conducted in a real-life scenario to show proof-of-concept among V2X interference.