关键词: 零信任安全, 区块链, 访问控制, 粮食溯源, 信任评估

Abstract: Aiming at the problems of malicious access, untrustworthy data sources, and identity forgery in the existing blockchainbased grain traceability model, a blockchain access control model for grain traceability based on a zerotrust mechanism is proposed. Based on the zerotrust security model and the concept of “never trust, always verify”, the blockchain is combined with tokenbased access control (TBAC). Using tokens as credentials to access resources, while introducing user trust analysis, establishing a dynamic and flexible authorization mechanism to achieve finegrained access control. Adding the blockchain smart contract to guarantee the automatic and trustworthy judgment of access control, TBAC is utilized to realize tokenbased access control; secondly, based on the user’s access behavior, Fuzzy Hierarchical Hierarchy Analysis (FAHP) is used so as to obtain the calculation method of the user’s trust value and to design the corresponding access control policy. Experimental results show that the method can correctly and efficiently respond to access requests, and dynamically grant users access rights on the basis of ensuring effective access to grain traceability data, realizing safe and reliable data access control.

Key words: zerotrust security, blockchain, access control, grain traceability, trust assessment