Decentralized access control technique with multi-tier authentication of user for cloud storage

The information kept in cloud is greatly sensitive. Security and privacy are two leading issues that often ascend in cloud computing. The objective of the research is to provide security and authentication of cloud data. So, we put forward with a novel decentralized access control scheme aimed at securely storing the data onto the cloud with multiple Key Distribution Center (KDC) based and multi-tier based authentication of user. In conjunction with cryptography to enrich the data security that is to be kept in the cloud we use steganography. In the proposed organization, irrespective of user's identity the cloud confirms the genuineness of the sequence prior to data storage. Our work likewise has the additional element of access control where just legitimate clients can decrypt the kept data and view the equivalent. The scheme supports multiple writing of data into cloud and multiple reading of information kept in the cloud. As a novelty we have introduced hidden attributes, accordingly the Cloud Service Provider (CSP) along with the KDC is unaware of user details and also a multi-tier based authentication to expand the authentication of user.