Abstract

With cloud data services, it is common place for data to be not only stored in the cloud, but also shared across multiple users. Unfortunately, the integrity of cloud data is subject to skepticism due to the existence of hardware/software failures and human errors. With our mechanism, the identity of the signer on each block in shared data is kept private from public verifiers, who are able to efficiently verify shared data integrity without retrieving the entire file. In addition, our mechanism is able to perform multiple auditing tasks simultaneously instead of verifying them one by one. However, public auditing on the integrity of shared data with these existing mechanisms will supports public auditing on shared data stored in the cloud that exploit ring signature to compute verification metadata needed to audit the correctness of shared data. So that a third party auditor (TPA) is able to verify the integrity of shared data for users without retrieving the entire data. Meanwhile, the identity of the signer on each block in shared data is kept private from the TPA it also able to perform multiple auditing tasks simultaneously instead of verifying them one by one. In this paper, we proved the data freshness (proved the cloud possesses the latest version of shared data) while still preserving identity privacy. In this proposed system mainly focus on traceability, which means the ability for the group manager (i.e., the original user) to reveal the identity of the signer based on verification metadata in some special situations. It’s based on ring signatures, where the identity of the signer is unconditionally protected.

Paper Details