A dynamic and secure smart grid data aggregation scheme

The rapid growth of smart grids has led to large-scale deployment of smart meters that continuously report fine-grained electricity consumption data. While homomorphic encryption enables privacy-preserving aggregation, existing schemes typically assume static participation and rely on per-user signature verification, resulting in scalability bottlenecks and poor robustness when smart meters join or leave dynamically. To address these limitations, this paper proposes DUDA, a dynamic and secure data aggregation scheme that integrates Paillier homomorphic encryption with ciphertext re-randomization and SM2 batch signature verification. DUDA supports dynamic user participation without rekeying, provides unlinkability across reporting rounds, and significantly reduces verification cost at edge servers. Security analysis demonstrates confidentiality, integrity, authentication, and robustness against replay and forgery attacks. Experimental results show that DUDA achieves efficient communication and computation compared to related work. These findings confirm that DUDA is lightweight, scalable, and suitable for real-world smart-grid deployments with frequent user churn.