An Analytical View of Revocable Attribute Based Encryption Schemes

Cryptographic techniques are a promising solution in the untrusted environment to share data securely. Traditional cryptographic techniques are not a suitable choice for secure data transfer in a cloud-based environment. Attribute based encryption schemes enabled secure data transfer and one-to-many encryptions possible for cloud and IoT applications. CPABE, one of the variants of ABE is studied by various researchers to regulate the access control of sensitive data uploaded on the distrustful cloud. Issues of CPABE schemes particularly for lightweight devices need more attention from researchers. A dynamic environment, where users join and leave frequently needs an efficient CPABE scheme to handle revocation under both single authority and multi-authority schemes. Researchers have either highlighted or proposed solutions to user revocation or attribute revocation and have also proposed CPABE schemes addressing computational cost, particularly for resource-constrained devices. In this paper, the revocation ability of various CPABE scheme are outlined and reviewed. The paper also studied the methodology used to address the user and attribute revocation by the existing schemes and compared the schemes on various resource-constrained devices and cloud storage criteria. Finally, the paper discussed the challenges which need to be further investigated and possible solutions for an efficient revocable CPABE scheme.