Attribute-Based Access Control Scheme for Security of Cloud Storage Systems Using RNS Cryptography

Emerging features of the cloud storage services enables data owners to store their big data in the cloud and provide the data access to the users. As privacy and security of the cloud server is not ensured, an Attribute-Based Encryption (ABE) a promising technique for data access control in cloud storage is utilized in this project. Attribute-based encryption, especially for cipher text-policy attribute-based encryption, can fulfil the functionality of fine-grained access control in cloud storage systems. In the proposed scheme, any user can recover the outsourced data if and only if this user holds sufficient attribute secret keys with respect to the access policy and authorization key in regard to the outsourced data. Both the size of cipher text and the number of pairing operations in decryption are constant, which reduce the communication overhead and computation cost of the system. Residue Number Systems (RNS) are useful for distributing large dynamic range computations over small modular rings, which allows the speed up of computations. RNS algorithm will be used for the encryption and decryption process involved, which can be used to achieve performance improvement as the arithmetic involves smaller numbers and can be done in parallel. This ensures the system is very fast, most reliable and is executed with the least computational costs.