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.

I. Background

Coding-based group signatures have become an important research topic in recent years. Since the seminal work of Alamelou et al. [1], several different optimizations have been proposed by various scholars to improve the security and implementation efficiency of the original scheme, as well as to support richer functional requirements. However, most of the existing constructs are only applicable to work in predefined static groups, i.e., the identity and number of people in the group are fixed during the initial setup phase, and dynamic updates (dynamic joining or dynamic revocation) of group members cannot be realized during the operation of the scheme [2]. There are only a few solutions that support semi-dynamic updating of group members (i.e., they can only realize one of the functions of “joining” by users or “revoking” by group members), and there is a lack of solutions that support fully dynamic updating of group members r31.