Improved PBFT Consensus Algorithm Based on Reputation Value for IoT

Abstract

Blockchain, as a decentralized distributed ledger technology, offers secure data exchange and reliable identity authentication for Internet of Things (IoT) devices, introducing new ideas for IoT development. Practical Byzantine Fault Tolerance (PBFT) is a widely used consensus algorithm that is well-suited for the IoT environment due to its low computing power requirements. However, the vast number of devices in the IoT presents a challenge. PBFT necessitates inter-node communication, which leads to decreased scalability as the number of devices grows. To overcome these IoT limitations, this paper proposes an improved PBFT algorithm based on reputation value. Nodes are evaluated and assigned levels according to their reputation values, with higher level nodes being chosen to engage in the consensus process, thereby minimizing the risk of malicious nodes participating. The primary node is unpredictably chosen from high-reputation nodes using random numbers. This approach also simplifies the consensus algorithm process and reduces communication complexity. Experimental findings indicate that the reputation value-based improved PBFT algorithm can diminish communication overhead and consensus delay.