A Review of Approaches to Achieve Data Storage Correctness in Cloud Computing Using Trusted Third Party Auditor

Built on the fundamental concepts of grid, cluster & distributed computing and following the evolution from mainframe computers to client/server models, Cloud computing is a novel paradigm where computing resources are provisioned on demand. By outsourcing computing and storage requirements to Cloud, user enjoys numerous benefits, such as cost saving through pay for you use model, flexibility & scalability, to name a few. But, as the data stored on the cloud is not under the direct possession of the user, many new security challenges are to be addressed. Data integrity issue is one of them where client's data may be tampered by unauthorized entities, or sometimes by the cloud service provider, intentionally or accidentally. Proposed approaches for data integrity verification fall under two broad categories, first which makes use of Trusted Third Party Auditor (TTPA) and other which does not exercise TTPA. In this work, we make an exhaustive review of several recently proposed schemes which utilize TTPA.