Achieve Data Security In Cloud Computing

Security and privacy are very important issues in cloud computing, we propose a new Data sharing has never been easier with the advances of cloud computing, and an accurate analysis of the shared data provides an array of benefits to both the society and individuals. Data sharing with a large number of participants must take into account several issues, including efficiency, data integrity and privacy of the data owner. Ring signature is a promising candidate to construct an anonymous and authentic data sharing system. It allows a data owner to anonymously authenticate his data which can be put into the cloud for storage or analysis purpose. Yet the costly certificate verification in the traditional public key infrastructure (PKI) Setting becomes a bottleneck for this solution to be scalable. Identity-based (ID-based) ring signature, which eliminates the process of certificate verification, can be used instead. There are three users: creator, reader & writer. Creator receives a token from a trustee, i.e. organization after giving ID to the trustee. There was multiple of Key Distribution Centre (KDC) which can be scattered. A creator gives their token to one or more KDC's then creator receives keys for encryption & decryption and for signing from KDC's. The message is encrypted under an access policy which means it decides who can access the data stored in the cloud. Creator decides on a claim policy to prove her authenticity and signs the message under this claim. The cipher text is sent to the cloud. The cloud verifies the signature and stores the cipher text. When a reader wants to read, the cloud sends cipher text. If the user has attributes matching with access policy, it can decrypt and get back the original message.