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A Study of Attribute-based Proxy Re-encryption Scheme in Cloud Environments

Attribute-based proxy re-encryption (ABPRE) scheme is one of the proxy cryptography, which can delegate the re-encryption capability to the proxy and re-encrypt the encrypted data by using the re-encryption key. ABPRE ex-tending the traditional proxy cryptography and attributes plays an important role. In ABPRE, users are identified by attributes, and the access policy is designed to control the user's access. Using ABPRE can have these advantages: (i) The proxy can be delegated to execute the re-encryption operation, which reduces the computation overhead of the data owner;(ii) The authorized user just uses his own secret key to decrypt the encrypted data, and he doesn't need to store an additional decryption key for deciphering;(iii) The sensitive information cannot be revealed to the proxy in re-encryption, and the proxy only complies to the data owner's command. In this paper, we survey two various access policy attribute-based proxy re-encryption schemes and analyze these schemes. Thereafter, we list the comparisons of them by some criteria.