Byzantine Fault Tolerance Consensus Protocol for IoT Devices

Abstract

Blockchain relies on a consensus method for agreeing on any new data. Most of the consensus methods which are currently used for the blockchain require high computational power and thus are not apt for resource-constrained systems. Byzantine Fault Tolerant (BFT) based consensus ensures that the blockchain network will continue to operate even in the presence of malicious or failure nodes, thus providing reliability. A typical Internet of Things (IoT) network consists of several devices which have limited computational and communications capabilities. Most often, these devices cannot perform intensive computations and are starved for bandwidth. Therefore, an improved BFT consensus algorithm is proposed in this paper to make it applicable for resource constrained IoT devices and networks. Firstly, by analyzing the architecture and core processes of BFT implementation, the HotStuff, factors affecting its adoptability in blockchain based IoT networks were identified. Secondly, an optimized tree-based HotStuff with sharding and latency compensation techniques is proposed. Finally, the improved consensus scheme is tested and analyzed. Our results show that the scheme significantly improves the performance of HotStuff and makes it suitable for utilization in blockchain IoT networks.