Nune, Srineevas (PhD)Gebregziabher, Tesfamichael2018-06-292023-11-042018-06-292023-11-042015-07http://etd.aau.edu.et/handle/123456789/4914According to a recent survey by Iternational Data Corporation [63], 75% of today’s digital data are duplicated copies. To reduce the unnecessarily redundant copies, the storage servers would handle duplication (either at a file level or chunks of data sized 4KB and larger). Deduplication can be managed both at the server-side and the client-side. In order to identify duplicated copies, it is required that files be un-encrypted. However users may be worried about the security of their files and may want their data to be encrypted. However encryption makes cipher text indistinguishable from theoretically random data, i.e., encrypted data are always distributed randomly, so identical plaintext encrypted by randomly generated cryptographic keys will very likely have different cipher texts which cannot be de-duplicated. In this research, a method that resolves the conflict between de-duplication and encryption is presented. Keywords - Cloud Storage, Client-side de-duplication, Proof of Ownership, File Server, Security, Secure Hash Standard, Advanced Encryption Standard, Windows Communication Foundation, Windows Presentation Foundation, and Dot Net FrameworkenCloud StorageClient-side de-duplicationProof of OwnershipFile ServerSecuritySecure Hash StandardAdvanced Encryption StandardWindows Communication FoundationWindows Presentation FoundationDot Net FrameworkThesis