An Auditable and Efficient Prepaid Scheme with Privacy Preservation in Smart Grids.

Existing security and privacy preserving schemes have too much wastage in token-based prepaid smart grids. In this paper, we propose a novel token concept and construct a security and privacy preserving prepaid scheme based on the power request model. In the proposed scheme, honest consumers keep their anonymity, while consumers who send used tokens can be tracked for law enforcement and maintenance purposes. In addition to security and privacy preservation, the computational cost of verification is independent of the number of tokens based on the novel token concept in the power request model. Therefore, the number of points can be the basic unit in order to minimize the wastage. Finally, we prove the security features and demonstrate the performances of our scheme.