关键词: 大数据安全, 属性加密, 访问结构, 策略隐藏, 访问控制

Abstract: The development of artificial intelligence depends on the development of cloud computing, at the same time, the security of artificial intelligence is closely related to the security of large data in the cloud. At Present, the ciphertext policy attribute-based encryption (CP-ABE) scheme is considered to be one of the most effective methods to achieve fine-grained access control of data in cloud. In the CP-ABE scheme, the access policy is often associated with the ciphertext. But sometimes, the access policy itself is also the important sensitive information, and access policies stored in the cloud in the form of clear text will also cause the users’ data revealed. In response to this problem, an efficient improved CP-ABE scheme is presented, which can hide the access policy. It can make both the attribute hiding and the secret sharing be applied to the AND-gate structure at the same time and then according to the composite order bilinear groups. Therefore, the user’s specific attribute value will not be disclosed to any other third party, thus we effectively protect the user’s privacy. In addition, through the experimental verification and data analysis, our scheme not only achieves the hidden of complex access structure，but also makes the ciphertext time shortened and decryption efficiency improved.

Key words: security of large data, attribute based encryption (ABE), access structure, hidden policy, access control