A multi-authority aggregate signature scheme for privacy-preserving and efficient message authentication in the smart grid

Abstract Smart grid systems use communication infrastructure and embedded devices to achieve data communication between devices and control centers. Ensuring the secure transmission and privacy protection of user electricity consumption data is a core challenge facing smart grids. However, existing authentication schemes often suffer from centralized bottlenecks, limited scalability, and insufficient privacy protection. This paper proposes a Multi-Authority Privacy-Preserving Aggregate Signature scheme (MAPS-G) specifically for smart grid environments. A distributed multi-authorization architecture is used to eliminate single points of failure, and the identity of devices is protected by an anonymous mechanism. To further reduce communication and computational overheads, an aggregator is introduced to batch verify messages using the aggregate signature technique. At the same time, a pseudonym update strategy is designed to ensure the unlinkability between different sessions. Security analysis shows that the proposed scheme is robust in terms of privacy protection and resistance to common attacks. Performance analysis experiments show that the proposed scheme significantly outperforms existing models in terms of computation, communication, and energy efficiency, and is suitable for resource-constrained devices such as smart meters.