SEDS: secure and efficient server-aided data deduplication scheme for cloud storage

Data deduplication is frequently used by many cloud service providers (CSPs) for efficient storage management. This process facilitates CSPs not to store the duplicate copies of a file. However, as data privacy is critical, data owners encrypt their data before outsourcing. Convergent encryption techniques have been proposed to enable deduplication over outsourced encrypted data. In this paper, we propose a server-aided data deduplication scheme for cloud storage, which supports duplication check across key servers. The most attractive feature of this scheme is the generation of fixed-size ciphertext regardless of the number of key servers. We showed that the proposed scheme achieves better performance than previous efforts both theoretically and experimentally. Further, we proved the security of the proposed scheme.