Privacy-Preserving Multi-Authority Attribute-Based Data Sharing Framework for Smart Grid

In smart power grid systems, real-time electricity data sharing can bring many benefits. However the security and privacy challenges have been a concern. This is because shared data may contain some private and sensitive information of data owners or users. So it has been an important issue to balance data utilization, data privacy and users privacy. Privacy-preserving multi-authority attribute-based encryption (MA-ABE) is a promising tool to tackle this issue, but it cannot be directly applied to addressed scenario of smart power grid systems. In this paper, we propose a framework to achieve secure data sharing in smart grid. The scheme uses the technique of inner product encryption (IPE). Under this framework, the access policy and the attribute set are fuzzy by converting them into two vectors. Only when the two vectors are orthogonal, users can successfully obtain the sharing data. Besides, our scheme allows that the threshold access policy only involves attribute name indexes, and sensitive attribute values are not sent along with the shared data so the attribute privacy is preserved. In addition, in order to improve efficiency, our scheme adds a testing phase to avoid the unnecessary operation before recovering data. Finally, our performance analysis and experiments confirm the merits of the proposed framework.