Abstract: The data outsourcing development challenges the approaches of traditional access control architectures such as reference monitor; that a trusted server is in charge of describing and enforcing access control policies. The main scope of the project is used to deliver the user data in the third party area for on demand access. The user access the details as privilege level based on access control. The dual encryption is processed in the cloud environment which is varied form one group to another for secure process. The paper propose a novel algorithm namely ciphertext-policy attribute-based encryption to enforce access control guidelines with efficient attribute and user revocation capability. Dual encryption mechanism which takes advantage of the attribute-based encryption and selective group key sharing in each attribute group. The ciphertext-policy EABE (CP-ABE) provides a scalable way of decoding data such that the encryptor defines the attribute set that the decrypt or needs to possess in order to decrypt the ciphertext. Thus, different users are permitted to decrypt different pieces of data per the security policy. This effectively eliminates the need to trust on the storage server for preventing unauthorized data access.

Keywords: Cloud Computing, Secure Data Sharing Scheme, Certificate Authorities, Untrusted cloud, Ciphertext-policy Attribute Based Encryption.