Secure query processing for smart grid data using searchable symmetric encryption

In the last decade, the smart grid has utilized many modern technologies and applications compared with the conventional grid. Cloud computing offers numerous managed services and storage solutions for smart grid data. To balance security, privacy, efficiency, and utility, more efforts should be made to keep up with the rapid evolution of technology. Searchable encryption techniques are widely considered an intelligent solution to ensure data privacy and security while maintaining the functionality to search over encrypted data. In this paper, we propose a more reliable and efficient searchable symmetric encryption scheme for smart grid data. It is a dynamic keyword searchable scheme that uses a symmetric cipher based on a key hashing algorithm (DKS-SCKHA) to generate a secure index. This scheme eliminates the false-positive issue associated with the use of bloom filters and narrows the scope of the retrieved search results. Additionally, it efficiently supports both partial and exact query processing on the encrypted database. Both theoretical and security analyses demonstrate the efficiency and security of the DKS-SCKHA scheme compared to other previous schemes. Comprehensive experiments on a smart grid dataset showed that the DKS-SCKHA scheme is 35-68% more efficient than the schemes compared in this paper. The DKS-SCKHA scheme supports three keyword search scenarios: single, conjunctive, and disjunctive. Furthermore, the DKS-SCKHA scheme is extended to support dynamic fuzzy keyword search on the encrypted database (DEFKS-SCKHA). We evaluated the security and efficiency of the DEFKS-SCKHA scheme through security analysis and experimental evaluation. Theoretical analysis shows that the proposed scheme is secure against known-ciphertext and known-background attacks.