An Improved Remote Data Possession Checking Protocol in Cloud Storage

摘要

In cloud computing, clients put the large data files on the untrusted cloud storage server, how to ensure the integrity of the outsourced data becomes a big problem.To address this issue, Hao et al. proposed a protocol which supports public verifiability and data dynamics. However, Hao et al.'s protocol suffers from two drawbacks. First, Hao et al.'s protocol is insecure and cannot resist the active adversary. Second, Hao et al.'s protocol only supports fixed-sized blocks as basic unit. As a result, the insertion of short message will cause a considerable waste of storage space. In this paper, we propose an improved remote data integrity checking protocol that can support variable-sized blocks. Besides, the improved protocol can resist the attack of the active adversary, and it is obvious to verify that the improved protocol still preserves the properties of Hao et al.'s protocol such as public verifiability and privacy preserving auditing.