PADP: A parallel data possession audit model for cloud storage

Data security and integrity problems are the most important issues that customers of cloud storage need to concern. In this paper, we propose a parallel audit model for data possession (PADP) in distributed cloud storage environment. The model utilizes the virtues of both a provable data possession (PDP) model and a data possession audit (DPA) model, and adopts a third-party auditor to separate users from storage service providers(SSP).Through adding the audit log mechanism, it can significantly reduce the storage and computation overhead of data possession audit(DPA) on the basis of fully ensuring the safety of audit process. Moreover, according to the characteristics of parallel computing in cloud storage environment, we propose a data possession prove algorithm called MapReduce-based Parallel Challenge Proof Generation Algorithm(MR_PCPGA) by improving the data possession prove algorithm based on homomorphic label in PDP model. Extensive security analysis and experimental results show the proposed schemes are provably secure and highly efficient in distributed cloud storage environment.