DeDOP: Deduplication with cross-server Ownership over encrypted data

The data deduplication is a standard practice among cloud service providers. The deduplication process allows storage servers to utilize limited storage capacity efficiently. The deduplication process is challenging when the data are in encrypted form. There are various data deduplication schemes for encrypted data. However, they do not consider a cross-server ownership issue. In this paper, we present a data deduplication scheme, DeDOP, for encrypted data, which also solves cross-server ownership issues. The scheme can detect two almost the same file uploaded by two different users on different storage servers in the system. If the fraction of the data match in two files is more than a certain threshold, then we say files are almost the same. The scheme provides tag consistency, which allows the system to detect data faking attacks where an adversary tries to upload fake data under the different tags in the system.