Secure and Membership-Based Data Sharing Scheme in V2G Networks

Vehicle-to-grid (V2G) network is an emerging network environment that can improve grid efficiency and alleviate fluctuations caused by renewable energy access to the grid. However, security and efficiency of V2G network is a very challenging and important factor in the case of large-scale electric vehicles (EVs) access to the grid. In this paper, we propose a secure and membership-based data sharing scheme in V2G networks. This scheme employs the online/offline ciphertext policy attribute-based encryption mechanism combined with fog computing, thus preserving data privacy and saving system resources. Concretely, the heavy computational operations of encryption and decryption are performed by the fog devices in offline encryption phase and decryption phase, respectively. What's more, the service information is divided into multiple parts in term of different membership levels and is encrypted by the control center (CC) through different access policy. The ciphertext can only be decrypted when the EV has a set of attributes that satisfy the corresponding membership level of access policy. Security and performance analyses demonstrate that the proposed scheme not only protects data privacy, but also saves the computational costs of CC and EV. Therefore, our scheme is more suitable for the deployment and adoption of V2G networks.