Secure and Efficient Deduplication for Cloud Storage with Dynamic Ownership Management

Cloud storage services have become indispensable in resolving the constraints of local storage and ensuring data accessibility from anywhere at any time. Data deduplication technology is utilized to decrease storage space and bandwidth requirements. This technology has the potential to save up to 90% of space by eliminating redundant data in cloud storage. The secure data sharing in cloud (SeDaSC) protocol is an efficient data-sharing solution supporting secure deduplication. In the SeDaSC protocol, a cryptographic server (CS) encrypts clients' data on behalf of clients to reduce their computational overhead, but this essentially requires complete trust in the CS. Moreover, the SeDaSC protocol does not consider data deduplication. To address these issues, we propose a secure deduplication protocol based on the SeDaSC protocol that minimizes the computational cost of clients while leveraging trust in the CS. Our protocol enhances data privacy and ensures computational efficiency for clients. Moreover, it dynamically manages client ownership, satisfying forward and backward secrecy.