Blockchain‐based smart and secure manufacturing systems

Abstract In the current data sharing environment of smart manufacturing systems, there is a lack of a transparent, open, and fair interaction environment, and there exists a serious imbalance in data sharing and transmission, which leads to data trust issues. To address this challenge, we propose a fine‐grained access control method for IoT data sharing based on blockchain technology (the Bayesian information criterion [BIC] scheme for IoT data sharing). This approach includes ex‐ante supervision and authentication of data sources, fine‐grained access control during data usage, and ex‐post tracking of malicious users. Firstly, a system model is built, and symmetric encryption is used to encrypt the data in order to improve computational efficiency. Subsequently, scheme design and algorithm design are carried out to encrypt the symmetric key using ciphertext‐policy attribute‐based encryption to achieve one‐to‐many data sharing, which greatly reduces the number of repeated encryptions and computational overheads. The data owner uploads the encrypted data to the cloud server, and the data user must hold the token generated by the blockchain to interact with the cloud and obtain the corresponding information. The results show that the BIC scheme not only ensures the legitimacy and security of data access but also locks up and traces malicious users who may have compromised their private keys, preventing illegal data sharing and key misuse; it offers significant advantages in terms of storage efficiency and time consumption, and also facilitates a flexible and secure data sharing process.