Efficient audit service outsourcing for data Integrity in clouds

Cloud-based outsourced storage relieves the client’s burden for storage management and maintenance by providing a comparably low-cost, scalable, location-independent platform. However, the fact that clients no longer have physical possession of data indicates that they are facing a potentially formidable risk for missing or corrupted data. To avoid the security risks, audit services are critical to ensure the integrity and availability of outsourced data and to achieve digital forensics and credibility on cloud computing.

Provable data possession (PDP), which is a cryptographic technique for verifying the integrity of data without retrieving it at an untrusted server, can be used to realize audit services. In this paper, profiting from the interactive zero-knowledge proof system, we address the construction of an interactive PDP protocol to prevent the fraudulence of prover (soundness property) and the leakage of verified data (zeroknowledge property).

We prove that our construction holds these properties based on the computation Diffie–Hellman assumption and the rewind able black-box knowledge extractor. We also propose an efficient mechanism with respect to probabilistic queries and periodic verification to reduce the audit costs per verification and implement abnormal detection timely. In addition, we present an efficient method for selecting an optimal parameter value to minimize computational overheads of cloud audit services. Our experimental results demonstrate the effectiveness of our approach.

Existing System:

To securely introduce an effective third party auditor (TPA), the following two fundamental requirements have to be met: 1) TPA should be able to efficiently audit the cloud data storage without demanding the local copy of data, and introduce no additional on-line burden to the cloud user 2) The third party auditing process should bring in no new vulnerabilities towards user data privacy.

Proposed System:

In this paper, we utilize the public Provable data possession (PDP), which is a cryptographic technique for verifying the integrity of data without retrieving it at an untrusted server; can be used to realize audit services. It with random mask technique to achieve a privacy-preserving public auditing system for cloud data storage security while keeping all above requirements in mind to support efficient Handling of multiple auditing tasks, we further explore the technique of bilinear aggregate signature to extend our main result into a multiuser setting, where TPA can perform multiple auditing tasks simultaneously. Extensive security and performance analysis shows the proposed schemes are provably secure and highly efficient. We also show how to extent our main scheme to support batch auditing for TPA upon delegations from multi-users.


  • Audit Service System
  • Data Storage Service System
  • Audit Outsourcing Service System
  • Secure and Performance Analysis

Tools Used:

Front End : ASP.Net with C#
Back End : SQL Server 2005