In Attribute-based Encryption (ABE) scheme, attributes play a very important role. Attributes have been ex-ploited to generate a public key for encrypting data and have been used as an access policy to control users' access. The access policy can be categorized as either key-policy or ciphertext-policy. The key-policy is the access structure on the user's private key, and the ciphertext-policy is the access structure on the ciphertext. And the access structure can also be categorized as either monotonic or non-monotonic one. Using ABE schemes can have the advantages: (1) to reduce the communication overhead of the Internet, and (2) to provide a ¯ne-grained access control. In this paper, we survey a basic attribute-based encryption scheme, two various access policy attribute-based encryption schemes, and two various access structures, which are analyzed for cloud environments. Finally, we list the comparisons of these schemes by some criteria for cloud environments.
International Journal of Network Security,15(4):231-240.