摘要：AbstractInternet of Things (IoT) networks are large peer-to-peer networks of small devices that require a competent security system that is scalable and adaptable to the limited resources of the IoT devices. Node authentication is a crucial part of IoT security. The current authentication solutions require a centralized trusted party for authentication, which presents a single point of failure. Blockchain as a peer-to-peer network with decentralized authentication can provide a decentralized solution for node authentication. In existing literature, most blockchain applications in IoT are connected to existing blockchain networks by more computationally capable devices, thereby limiting their adaptability for IoT networks and presenting single point of failure problem. Considering the issues, this paper proposes a blockchain-based decentralized structure for authentication by arranging the IoT devices into clusters based on their computational capability, energy reserve and their location. The devices in each cluster are authenticated by a hierarchical structure of interconnected blockchains. To reduce the processing load we introduced a consensus protocol based on verifying identity-based encryption key signature of the device and its related cluster. The proposed structure simulation has shown a reduction of the processor and memory load of IoT devices. Further testing using Docker container network and Raspberry Pi devices network has shown that the proposed blockchain structure and consensus algorithm have reduced computational load. The analysis of the structure security and performance shows it offers comprehensive security protection while being lightweight and scalable.
