Comparable Attribute-Based Encryption
Data access control has been an increasing concern in the cloud environment where cloud users can compute, store and share their data. Ciphertext-Policy Attribute-Based Encryption (CP-ABE) can be used to provide a fine-grained access control for dynamic group formation in cloud-based data storage solutions. CP-ABE is ceeds to convert comparative attributes into a bit-wise monotone access tree structure to enforce expressive access control of encrypted data. Using CP-ABE scheme, the temporal comparison relies on bit-matching and incurs large sizes of data users’ keys and overhead, resulting in high computational costs in encryption and decryption. In some cases, multiple attribute domains are required by independent organizations, such that each organization can run an Attribute Authority to host its own attribute domain. From the perspective of the data owner, different attribute domains are at different levels of confidentiality.