Fully Dynamic Group Signature for Smart Grid

Smart grid is committed to transforming public energy networks into flexible and intelligent energy utilities, the great changes in operation and management methods of the smart grid also bring new challenges to the security of the power grid, especially the user's privacy protection issues. Frequent reporting of electricity usage data poses a great threat to users' privacy and security. Attackers may analyze and mine electricity usage data to obtain privacy information such as users' activity status, daily routines, and lifestyle habits. In this paper, we propose a real-time data collection and dynamic billing scheme for meters in smart grids based on dynamic group signatures. Therefore, an efficient and fully dynamic group signature scheme based on encoding is proposed by blinding information and simplifying the signature process, and its security is proven under a random oracle model. This scheme can dynamically add or delete group members without the need to frequently change the key information of other group members, only by calculating changes to the group's public information. The scheme is made forward secure by updating the private keys of group members over time. Based on the efficiency analysis conducted, this scheme has lower system overhead and shorter signature length, which makes it more suitable for open and low bandwidth communication environments.