Decentralized Anonymous Authentication Protocol with Conditional Privacy Preservation in V2G Networks

With the continuous increase in the number of electric vehicles (EVs), the new power system needs to comprehensively consider the fusion development of EVs and the power system. Vehicle-to-Grid(V2G) is a technology for electric vehicles to interact with the power grid as energy storage units. However, when electric vehicles are connected to the power grid, the V2G network will involve a large amount of privacy data exchange and sensitive charging/discharging transactions, directly threatening user privacy and security. For this reason, many scholars have focused on anonymous protocols. However, existing anonymous authentication protocols in V2G networks rely on a completely trusted third party. Once a third-party center is attacked, user data security and privacy security will no longer exist. Therefore, based on distributed key technology, we propose a decentralized anonymous authentication protocol with conditional privacy preservation. At the same time, a batch verification algorithm suitable for this protocol was proposed, further improving the authentication efficiency of local aggregators. Finally, security analysis and experimental analysis were conducted on the proposed protocol. The results indicate that our protocol has formal provable security and has lower computational and communication costs compared to existing protocols.