P3AKA: A PUF based privacy preserving authentication and key agreement framework for secure communication in vehicle to grid network

A traditional power grid integrates a Smart Grid (SG) technology to reduce greenhouse gases and increase the efficiency of energy transition. The Vehicle to Grid (V2G) is raised and combined with the SG network to fulfill these objectives of the SG technology. The two-way power flow in the V2G technology allows an Electrical Vehicle (EV) to charge its battery and discharge surplus energy back to the power grid through the Charging Stations (CSs). During the energy transfer, an EV shares identity, location, and charging preferences with the CS through an insecure channel. It raises significant security and privacy vulnerabilities for the V2G network. In addition, the EV and CS are situated in an exposed location that may increase the risk of physical attack. Hence, there is a need to preserve the security and privacy of the EV and CS in the V2G network. Moreover, a lightweight security solution is necessary for the resource constrained CS and EV in the V2G network. Several authentication and key agreement protocols were suggested in the literature to overcome the security challenges in the V2G network. However, the existing approaches fail to maintain the session key secrecy and preserve from the physical attack. Thus, we propose a Physically Unclonable Function (PUF) based Privacy Preserving Authentication and Key Agreement (P3AKA) framework for the V2G network using lightweight cryptographic operations. PUF protects the CS and EV from the physical attack and other lightweight cryptographic functions safeguard the network from other security attacks. Security analysis of the proposed P3AKA framework represents that it protects the V2G network from potential security threats such as impersonation, replay, Man-in-The-Middle (MiTM), physical, and machine learning attacks. Further, it ensures user anonymity and non-traceability of the EV user. The formal security verification uses the ROR model and Scyther tool to verify the proposed P3AKA framework. It illustrates that the P3AKA framework successfully provides bidirectional authentication and session key secrecy in the V2G network. In addition, the performance analysis illustrates that the proposed P3AKA framework improves security with competitive overheads compared to existing relevant schemes.