A Novel Blockchain-Based Revocable Permission Management on CP-ABE Scheme

Relying on the characteristics of decentralized, tamper-proof, and traceable, blockchain technology has begun to be widely used in permission management. It can be used for access control by using smart contracts to distribute tokens. But also because of the immutability of the blockchain, it cannot dynamically revoke permission. This paper proposed an on-chain user permission management mechanism that could support automatic and active permission revocation. This model proposed an extended CP-ABE chain user permission management model, which realized the permission grant based on user attributes by smart contracts. Furthermore, on this basis, an extended CP-ABE permission revocation mechanism was proposed. The timestamp technology was used to realize the automatic revocation of permission, and the subset coverage algorithm was used to realize the active revocation of permission. A blockchain-based permission distribution model was built, and the permission revocation scheme was introduced into it to conduct experiments. Its performance was tested and analyzed. The experimental results showed that when the number of permission distributions is 1000, the delay is about 5 s. At the same time, the permission change is above 130TPS, which met actual application requirements.