Deduplication and Decentralized Access Control in Cloud with Efficient Public Auditing Mechanism

Cloud computing is a very important area which Permits client to remotely store their data into the cloud and enjoy the on-interest excellent applications and services. However in cloud computing, since the data is put away anyplace over the globe, the client organization has less control over the stored data. So here, security and privacy are very important things. The user should to validate himself / herself before beginning any transaction, and user privacy is also important so that the cloud or other user in cloud do not know the identity of user who stored the data. This is an access control system for data store away in cloud that gives anonymous authentication. In this scheme, the cloud confirms the user without knowing the users identity before storing data in the cloud by using ABS (Attributes Based Signature). The proposed scheme uses ABE (Attribute-Based Encryption) in which the attributes are match and according to matching attribute the various access control (Read, Write) are provide to user. Also for Integrity checking trusted outsider security service provider is used who does not store any data at its end, and its only confined to providing security service. Thus, enabling public auditability for cloud storage is of discriminating significance so that client can resort to a third-party auditor (TPA) to check the integrity of outsourced data and be effortless. In Proposed system the task of Key distribution is done in a decentralized way, for this more than one KDC are used who shares the same databases. The scheme not only verifies the integrity of data but also performs De-duplication of files. Moreover, this authentication and access control scheme is decentralized and robust, unlike other access control schemes designed for clouds which are centralized. The Experimental result show that the proposed system is more efficient in terms of data storage and security, and also it reduces the computation overhead of user by making the use of TPA.