Privacy-Preserving Public Auditing for Regenerating-Code-Based Cloud Storage

Abstract

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. Existing remote checking methods for regenerating-coded data only provide private auditing, requiring data owners to always stay online and handle auditing, as well as repairing, which is sometimes impractical. The proposed system, Privacy preserving public auditing scheme for the regenerating-code-based cloud storage is to solve the regeneration problem of failed authenticators in the absence of data owners with the help of proxy, which is privileged to regenerate the authenticators, into the traditional public auditing system model. Moreover, the design consists of a novel public verifiable authenticator, which is generated by a couple of keys and can be regenerated using partial keys. Thus, the scheme can completely release data owners from online burden. In addition, the randomized encode coefficients with a pseudorandom function is to preserve data privacy. Extensive security analysis shows that this scheme is provable secure under random oracle model and experimental evaluation indicates that this scheme is highly efficient and can be feasibly integrated into the regenerating code- based cloud storage.

 

Keywords: Cloud Storage, Regenerating Codes, Public audit, Privacy Preserving, Proxy, Provable secure.