Implementation of Data Privacy Framework for Public Cloud Storage

Abstract

Using Cloud Storage, users can remotely store their data and enjoy the on-demand high quality services and applications from a shared pool of configurable computing resources, without the burden of local data storage and maintenance. However, to protect outsourced data in cloud storage against corruptions, adding fault tolerance to cloud storage together with data integrity checking and failure reparation becomes critical. Recently, regenerating codes have gained popularity due to their lower repair bandwidth while providing fault tolerance. Moreover, users should be able to just use the cloud storage as if it is local, without worrying about the need to verify its integrity. Many mechanisms dealing with the integrity of outsourced data without a local copy have been proposed under different system and security models up to now Thus, enabling public audit ability for cloud storage is of critical importance so that users can resort to a third party auditor (TPA) to check the integrity of outsourced data. To securely introduce an effective TPA, the auditing process should bring in no new vulnerabilities towards user data privacy, and introduce no additional online burden to user. Many mechanisms dealing with the integrity of outsourced data without a local copy have been proposed under different system and security models up to now. In this paper, we propose a secure cloud storage system supporting privacy-preserving public auditing. We further extend our result to enable the TPA to perform audits for multiple users simultaneously and efficiently. Extensive security and performance analysis show the proposed schemes are provably secure and highly efficient.