Privacy Preserving Access Control Mechanism In Public Clouds
Fine-grained access control mechanisms on secure data in the cloud are based on encryption of the data in
fine-grained approach. In these approaches, owners of the data in cloud encrypt the data before uploading them on the cloud
and re-encrypt the data whenever user credentials change. Owners of the data also known as Data owners thus generate high
costs in terms of communication and computation. A better approach should be used that delegates the enforcement of
fine-grained access control to the cloud, minimizing overhead at the data owners. Also assure data confidentiality from the
cloud. Our technique is based on two layers of encryption that targets such requirement. In the proposed approach, the data
owner performs a coarse-grained encryption, while the cloud performs a fine-grained encryption on the owner encrypted data.
A challenge is to decompose access control policies (ACPs) such that the two layer encryption can be made. We also utilize an
efficient group key management scheme that supports communicative ACPs. Our system assures the confidentiality of the data
and preserves the privacy of user’s data from the cloud while delegating most of the access control enforcement to the cloud.
Keywords- Access Control, Encryption, Identity, Policy Decomposition.