Power data attribution revocation searchable encrypted cloud storage

Grid business data contains a large amount of electricity data customer privacy data, serving more than 1.1 billion people, involving personnel, financial, material, assets and other ten areas of data resources. The existing grid data has the security problem of privacy leakage due to reverse analysis in the process of publishing, and the data permission is difficult to revoke. To address these problems, this paper proposes a CP-ABE (ciphertext policy attribute based encryption) cloud storage scheme with revocable attributes, which can ensure the security of attribute permissions, dynamic change of user attributes and complete protection of user privacy. The paper is based on a subset-covered attribute revocation technique, which generates a corresponding user tree for each user attribute to enable revocation of user attributes without updating the user key after revocation, reducing the corresponding computational overhead. Then, multiple attribute authorisation authorities are used to distribute and manage keys without introducing any other trusted authorities, protecting user privacy and avoiding security issues caused by a single attribute authorisation authority. Finally, a pre-decryption algorithm is designed to reduce the computational overhead of the user when decrypting. The security analysis yields that the scheme has ciphertext privacy and keyword privacy; the performance analysis finds that the scheme has low computation and communication overheads; the experimental analysis reflects that the scheme has low key storage overhead, ciphertext storage overhead and index storage overhead.