earticle

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The privacy of the information against the cloud was assured by the technique of encryption and the usage of approaches of conventional encryption is not enough to hold up the access control policies of fine-grained organizational enforcement. Throughout the initial encryption and subsequent re-encryptions, scheme of two layer of encryption was developed that diminishes the overhead sustained by the owner. During the addition or removal of identity attributes the owner has no need to re-encrypt the data since the essential re-encryptions were performed by the cloud to implement the access control policies and consequently the two layer of encryption approach reduces the overhead of computation and communication at the owner. In the approach of two layer of encryption, the time of running at the cloud is superior to that at the owner in view of the fact that the cloud performs encryption of fine grained while the owner only carries out coarse grained encryption.