Abstract: Cloud computing, with bringing convenience to consumer, also poses new security challenges to consumer data. Where the data integrity is one of the security issues that consumer worry about. We first analyse the deficiency of existing data integrity verification scheme in cloud storage environment, in which we can only validate the individual data file, then present a new improved scheme. The latter not only supports the integrity verification of multiplcreplication data,but also supports the data privacy protection in the process of validation. I3y security and feasibility analysis of improved scheme in more details,we indicate that the improved scheme is secure and effective.

Key words: Cloud storage, Data integrity, Privacy protecting, Multi-copy