A Fast Revocation Method in Attribute-based Encryption using DPVS

In the application of CP-ABE for data access control, one prominent drawback is the low efficiency in attribute revocation. Data owners and attribute authorities have to not only replace users' attribute private keys but also update the original ciphertext and the private keys of all other users with the same attribute to prevent the reuse of the original attribute private keys. Moreover, besides the significant computational overhead caused by attribute addition and revocation, user migration also demands attention. Given the complexity and rapidity of user changes, a scheme should be designed to accomplish the operation of addition and revocation of attributes or users with lower computational costs while ensuring forward and backward security of the system and preventing revoked users or keys from being reused to access new data. In this paper, we introduce DPVS to achieve efficient privilege management and policy hiding in the CP-ABE scheme. Experiments have demonstrated that our scheme reduces the computational overhead of user revocation and attribute revocation, improves the user decryption speed, and provides an additional policy hiding scheme for users to choose flexibly.