Smart contracts attribute-based access control model for security & privacy of IoT system using blockchain and edge computing

In order to solve the problem of data security and management between IoT edge nodes and massive heterogeneous devices, combined with the wide application of blockchain technology in distributed system data security management, a blockchain-based Internet of Things access control model (SC-ABAC) is proposed by combining smart contracts and attribute-based access control. The traditional consensus algorithm PoW (Proof of Work) and SC-ABAC access control management process are optimized. By quantitative analysis, the time to call contracts in the query process increases linearly, the time of the policy addition and judgment process is constant, and the energy consumption of the optimized consensus mechanism is smaller than that of the PoW unit. This model provides decentralized, fine-grained, and dynamic access control management in IoT environments, enabling distributed systems to reach consensus faster and ensure data consistency.