Dependable Decentralized Reputation Management System for Vehicular Ad Hoc Networks

Reputation management systems are essential for establishing trust among network users. They are tools for reinforcing cooperation and sanctioning malicious behavior. Their importance becomes a requirement in highly mobile and volatile environments, such as vehicular ad-hoc networks (VANET). In the present work, we propose a dynamic and decentralized reputation system that fits VANET characteristics like dynamism and volatility without conceding on security. The novel system uses blockchain for reputation information aggregation and storage and secure multiparty computation (SMC) to achieve privacy. Unlike previous VANET reputation systems, our system does not rely on a central authority to evaluate trustworthiness. Instead, it limits its role to maintaining the blockchain and system integrity leaving reputation evaluation to peers. It preserves feedback privacy in the presence of up to n − 2 dishonest parties and shows good performance. Remarkably, our system takes advantage of the infrastructure of VANET when vehicles are nearby while remaining fully functional in extra-urban areas.