Toward Ciphertext Policy Attribute Based Encryption Model - A Revocable Access Control Solution in Cloud Computing.

Cloud Computing is the most promising paradigm in recent times. It offers on-demand services to individuals and industries. However, outsourcing sensitive data to entrusted Cloud servers impedes the adoption of Cloud concept. Security presents the most important issue. Consequently, Cloud service provider should implement fine grained access control models. Ciphertext Policy Attribute Based Encryption (CPABE) is considered as one of the most appropriate approach in Cloud Computing environment. However, it suffers from revocation, data owner overhead and computational cost limitations. In this work, we propose a Revocable algorithm (R-CPABE). The main idea of this work is to divide the original data after publishing in cloud server. In case of user revocation, one single slice is affected. Data owner need to retrieve, re-encrypt and re-publish it. To confirm the safety of our solution, we provide a security analysis. To evaluate its efficiency, a performance evaluation is performed.