Byzantine fault-tolerant distributed access control mechanism for the Internet of things

With the widespread adoption of the Internet of things (IoT), the data volume handled by IoT devices has been growing rapidly, leading to a significant increase in data access demands. However, the wide geographic distribution of IoT devices, their heterogeneous networks, and the highly sensitive nature of the data pose severe challenges to efficient data management and secure access. Addresses IoT scenarios involving Byzantine nodes by investigating IoT access control technologies, a hierarchical blockchain network architecture was proposed which comprised a main cluster and multiple sub-clusters. Based on the computational power and communication rate of IoT devices, a node performance metric was defined to identify main cluster nodes and determine node association strategies to optimize system throughput. Within the constructed hierarchical blockchain network architecture, smart contracts were deployed to manage access control policies, including their definition, updates, deployment, and revocation. To enable IoT access control in scenarios with Byzantine nodes, an improved Paxos-Hotstuff hierarchical consensus algorithm was proposed, which comprehensively considered system consensus performance and complexity. In the proposed algorithm, the main cluster nodes execute an improved Paxos algorithm, while the sub-cluster nodes execute the Hotstuff algorithm. Simulation results validate the effectiveness of the proposed algorithm.