PEACS: A Privacy-Enhancing and Accountable Car Sharing System

Car sharing is gaining increased popularity in urban transportation which allows individuals to conveniently rent vehicles for short periods. Such systems, however, present considerable challenges to security such as unauthorized access and privacy data breaches, as service providers are able to track the precise mobility patterns of all customers. Nevertheless, efforts in solving the security and privacy concerns associated with car-sharing services are relatively few, in particular for a trade-off between privacy preservation and accountability of misbehaviors. In this work, we propose an efficient Privacy-Enhancing and Accountable Car Sharing System (PEACS), introduced to mitigate the aforementioned threats. PEACS primarily employs several key ingredients, including structure-preserving signatures on equivalence classes (J CRYPTOL’s 19), as well as two primitives designed in this paper, namely: signatures of knowledge and identity-based structure-preserving signatures with a tag on equivalence classes. Furthermore, we employ a bivariate polynomial function to establish a revocation mechanism that ensures accountability. We provide thorough security proof to demonstrate the security and privacy of PEACS. Comprehensive performance evaluation and comparison results point out that our proposed scheme is feasible in practical settings.