A Secure and Efficient Data Deduplication Scheme with Dynamic Ownership Management in Cloud Computing

Encrypted data deduplication is an important technique for eliminating duplicate copies of repeating data, and has been widely used in cloud storage to save storage space and network bandwidth. Recently, several deduplication schemes solving the privacy-preserving problem of dynamic ownership management have been proposed. However, these schemes suffer from low efficiency when the cloud user joining and revocation frequently go on, especially in the absence of a trusted third party. In this paper, we propose a novel server-side deduplication scheme for encrypted data in a hybrid cloud architecture, where a public cloud (Pub-CSP) manages the storage and a private cloud (Pri-CSP) plays a role as the data owner to perform deduplication and dynamic ownership management. Further, to mitigate the communication overhead we adopt a pre-verified accessing control approach to prevent the unauthorized cloud users from downloading data and use an initial uploader check mechanism to ensure only the first uploader needs to perform encryption. Our security analysis and performance evaluation demonstrate that our proposed scheme has better performance in terms of security, effectiveness, and practicability compared with other schemes.