Data access control is a challenging problem for the public Cloud storage system. Ciphertext policy attribute encryption (CPABE) has been adopted as a promising technology Provides flexible, fine-grained and secure data access control Cloud storage with honest and curious cloud server. However, In the existing CP-ABE scenario, the single attribute permissions You must perform timeconsuming user legitimacy validation Secret key distribution, resulting in a single point Performance bottlenecks when using CP-ABE Large cloud storage systems. The user may stay in Waiting for the queue to obtain its key for a long time, resulting in inefficient system. Although multiple permissions these have proposed access control programs The program still cannot overcome the shortcomings of the single point Bottlenecks and inefficiencies due to every fact. The authorities still independently manage disjoint attribute sets..

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