A Hybrid Cloud Approach for Secure Authorized Deduplication

Abstract

Data deduplication is one of important techniques for eliminating duplicate copies of existing data, and is widely used in cloud storage to minimize the amount of storage space and save bandwidth. To protect the confidentiality of available data while supporting deduplication, the convergent encryption technique is proposed to encrypt the data before outsourcing. To protect data security, this paper does make the first attempt to formally address the problem of authorized data deduplication. Different from traditional deduplication systems, the differential privileges of users are further considered in duplicate check besides the data itself. We also present different new deduplication constructions supporting authorized duplicate check in a hybrid cloud architecture. Security analysis demonstrates that our system is secure in terms of the definitions specified in the proposed security model. We implement a prototype of our proposed authorized duplicate check scheme and conduct test bed experiments using our prototype, As a proof of concept. We show that our proposed authorized duplicate check scheme incurs minimal overhead compared to normal operations.