Design of Blockchain-Based Multi-Domain Authentication Protocol for Secure EV Charging Services in V2G Environments

Multi-domain vehicle to grid (V2G) is a network environment in which numerous service providers offer charging and discharging services to EV users. This can enhance energy management and traffic flow for efficient intelligent transportation systems (ITS). However, the combination of multiple domains can suffer from various security vulnerabilities, highlighting the need for robust countermeasures. Moreover, existing multi-domain V2G protocols utilized a central trusted authority (TA) which can create a single point of failure (SPOF), or required high computational resources. In this paper, we propose a multi-domain authentication protocol for secure and efficient V2G services using consortium blockchain. The proposed protocol provides lightweight intra-domain authentication using hash functions and XOR operators. Furthermore, the proposed protocol ensures secure cross-domain authentication by integrating elliptic curve cryptography (ECC) and physical unclonable function (PUF). Therefore, the proposed protocol can establish trust, enable efficient communications, and prevent congestion at charging stations. To validate security robustness, comprehensive evaluations are conducted using "Real-Or-Random (ROR) model", "Scyther tool", and informal analyses. Comparative computational overheads of the proposed and related protocols are measured using "Multiprecision Integer and Rational Arithmetic Cryptographic Library (MIRACL)" testbed experiments. Additionally, a simulation of the practical deployment is conducted using "Network Simulator-3 (NS-3)". Results indicate that the proposed protocol can improve ITS by providing secure and efficient services for multi-domain V2G environments.