Fine-Grained Attribute-Based Encryption Scheme Supporting Equality Test

The data of user should be protected against untrusted cloud server. A simple way is to use cryptographic methods. Attribute-based encryption (ABE) plays a vital role in securing many applications, particularly in cloud computing. In this paper, we propose a scheme called fine-grained attribute-based encryption supporting equality test (FG-ABEET). The proposed scheme grants the cloud server to perform if two ciphertexts are encryptions of the same message encrypted with the same access policy or different access policy. Moreover, the cloud server can perform the equality test operation without knowing anything about the message encrypted under either access policy. The FG-ABEET scheme is proved to be secure under Decisional Bilinear Diffe-Hellman (DBDH) assumption. In addition, the performance comparisons reveal that the proposed FG-ABEET scheme is efficient and practical.