Abstract: Cloud Service Providers offer highly available storage and colossally computing resources at comparatively squat fee. The storage space provided may contain more number of repeated data. Inorder to reduce the storage space and eliminate the duplicates of data, Data Deduplication technique is being used. It is one of the method that eradicates duplicate copies of repeating data to reduce the storage space and save bandwidth. Inorder to protect the confidentiality of the data, Convergent Encryption Technique has been used. It outsource the data only after it is being encrypted using the convergent key. To protect the Data Security, Differential Authorized duplicate check is being used. The deduplication is done only by the authorized user. In traditional deduplication schemes, the disparity rights of users are further considered in duplicate check besides the data itself. The new deduplication constructions supports authorized duplicate check in a hybrid cloud architecture. The proposed system includes the VAST storage system that is used for storing the valuable and secret data. It thwarts the unauthorized user to steal the information from small pieces of the data. The hacker cannot attain the entire information from small part of information, since the data is stored in the form of manageable pieces of data.

Keywords: Convergent encryption technique, Authorized duplicate check, Private Cloud, Public Cloud, Deduplication, Privileges.