Privacy-Preserving Identity Management in Car Sharing

Car sharing is a typical smart city application that offers users a flexible rental option. However, the services pose privacy concerns since user identifications and real-time driving trajectories need to be shared. To address the issue, we introduce DPCS, a decentralized and privacy-preserving architecture in this chapter. DPCS replaces the traditional single trusted authority with multiple dynamic validation servers, enhancing system resilience with decentralized trusts. A key component of DPCS is a novel privacy-preserving identity management scheme. The scheme protects identity privacy through a distributed, dynamic approach, using a zero-knowledge proof protocol with public verification. Only the identities of misbehaving users can be traced by a consensus among the validation servers. Thorough security analysis and performance evaluations demonstrate that DPCS effectively enhances security and is efficient in terms of computation and communication.