An Auditing Protocol for Data Storage in Cloud Computing with Data Dynamics

Data integrity checking for cloud storage services has attracted widespread attention from academia and industry recently. However, some issues should be addressed in case the dynamic operations are considered, because the dynamic auditing schemes are vulnerable to replay attacks mounted by the malicious cloud servers, and also cannot support the multi-granular dynamic operations well. This paper proposes a hierarchical auditing protocol for data storage in cloud computing with data dynamics by incorporating the idea of Merkle Hash tree (MHT) and bilinear pairings technology. In this paper, the basic block has been divided into a number of smaller blocks by utilizing the hierarchical index structures, and every leaf of the Merkle Hash Tree is associated with multiple blocks, so our scheme can reduce the length of the Merkle Hash Tree effectively. The proposed scheme can not only meet the security demands of cloud storage services for data integrity, but also support the user to perform multi-granular dynamic operations. In addition, the communication costs of the dynamic operations derived from the user and the auditing operations derived from the auditor have been greatly reduced. Finally, security analysis and performance analysis show that our proposed scheme is secure and efficient.