A Robust Generic Multi-Authority Attributes Management System for Cloud Storage Services

Attribute Based Encryption (ABE) schemes face number of essential challenges for achieving data privacy in Cloud Storage Services (CSS). One crucial challenge is the existence of a single authority for attributes management. The second challenge is the lack of an efficient attribute revocation mechanism that prohibits an unauthorized access instantaneously after an attribute revocation is requested. The third challenge is the avoidance of using attribute revocation scenario as a mechanism for user revocation. In this paper, a robust generic multi-authority attributes management system is presented to overcome these challenges for CSS. The proposed system can be implemented using either Ciphertext Policy ABE (CP-ABE) or Key Policy ABE (KP-ABE) technique that possesses a specific set of characteristics. In addition, the proposed system presents a novel structure for user digital identity that prohibits the collusion between system users. Moreover, the proposed system does not oblige cooperation between the participated attributes authorities to accomplish any of the proposed system tasks. Furthermore, the attributes authorities can join or leave the proposed system without mandating the proposed system re-initialization. Finally, the presented performance measures prove the proposed system validity to accomplish all the specified goals with acceptable performance.