Survey on Ciphertext Policy Attribute-Based Encryption (CP-ABE) for Sharing Hierarchical Files

Ciphertext Policy Attribute-Based Encryption (CP-ABE) provides access control in owner’s hand in which the secret key of a user and the ciphertext are dependent upon attributes. The encryptor can fix the policy, which user can decrypt the encrypted message. The shared data files generally have the characteristic of multilevel hierarchy, particularly in the area of healthcare and the military. In order to explore the hierarchy structure of shared files an Efficient File Hierarchy Attribute-Based Encryption scheme (FH-CP-ABE) is proposed. The layered access structures are integrated into a single access structure, and then, the hierarchical files are encrypted with the integrated access structure. When two hierarchy files are shared, the performance of FH-CP-ABE scheme is better than CP-ABE’s in terms of encryption and decryption’s time cost, and CT’s storage cost.