A Charging and Discharging Data Privacy Protection Scheme for V2G Networks Based on Cloud–Fog-End

Due to the openness of the vehicle-to-grid (V2G) network, the upload of charging and discharging data faces severe security challenges such as eavesdropping, tampering, and forgery. These challenges can lead to privacy breaches, transmission delays, and service quality degradation. To address these issues, a V2G network architecture based on cloud–fog-end is designed, and a charging and discharging data privacy protection scheme is proposed. We employ a pseudonym mechanism to achieve the conditional privacy protection of electric vehicle (EV) users. We design a certificateless aggregate signcryption (CLASC) algorithm to guarantee the security of uploading the charging and discharging privacy data. The algorithm solves certificate management and key escrow issues, utilizes aggregate signature operations to save network bandwidth, and avoids complex computations like bilinear pairings and exponents. Additionally, the scheme delegates the aggregate verification process to the fog layer, thereby alleviating the computational burden on the cloud layer, decreasing transmission delays, and enhancing the efficiency and reliability of the V2G network. The analysis results indicate that the scheme not only meets the required security objectives, but also has lower computational and communication overheads, making it suitable for scenarios involving the charging and discharging of large-scale EVs in V2G networks.