Cloud

Clock-Based Proxy Re-Encryption Scheme in Unreliable Clouds

Download Now Date Added: Apr 2012
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In this paper, the authors propose a Clock-based Proxy Re-Encryption (C-PRE) scheme to achieve fine-grained access control and scalable user revocation in unreliable clouds. Their scheme, which is built on top of Cipher-text-Policy Attribute-Based Encryption (CP-ABE) and Proxy Re-Encryption (PRE), allows the data owner and the cloud to share a secret key in advance, with which the cloud can be delegated to re-encrypt data on behalf of the data owner. The main merit of their scheme is that the cloud can automatically re-encrypt data based on its internal clock without receiving any command from the data owner.