MHB*T based dynamic data integrity auditing in cloud storage

Integrity audit technology is proposed to protect data in remote cloud servers from being tampered with. However, the challenge is that the computational complexity is too large for users with resource-constrained devices during integrity verification. Also, many prior works lack support for dynamic operations. In this paper, a trusted third party is employed to complete the public auditing to reduce the computational complexity of users. Meanwhile, a trusted proxy server is employed to compute the tags under the delegation of the data owner. To improve the efficiency of data retrieval and support dynamic operations, a new authentication structure is proposed by combining Merkle Hash Tree and B* tree. Based on the new authentication structure, we propose a public integrity auditing scheme, which is secure against forge attacks under the assumptions of the discrete logarithm problem and the computational Diffie-Hellman problem in bilinear groups in the random oracle model. Security analysis and experiment results show that our scheme is provably secure and has low communication complexity and computational complexity.