CF-BFT: A Dual-Mode Byzantine Fault-Tolerant Protocol Based on Node Authentication

Abstract

The consensus protocol is one of the core technologies in blockchain, which plays a crucial role in ensuring the block generation rate, consistency, and safety of the blockchain system. Blockchain systems mainly adopt the Byzantine Fault Tolerance (BFT) protocol, which often suffers from slow consensus speed and high communication consumption to prevent Byzantine nodes from disrupting the consensus. In this paper, this paper proposes a new dual-mode consensus protocol based on node identity authentication. It divides the consensus process into two subprotocols: Check_BFT and Fast_BFT. In Check_BFT, the replicas authenticate the primary’s identity by monitoring its behaviors. First, assume that the system is in a pessimistic environment, Check_BFT protocol detects whether the current environment is safe and whether the primary is an honest node; Enter the fast consensus stage after confirming the environmental safety, and implement Fast_BFT protocol. It is assumed that there are nodes in total. If more than nodes identify that the primary is honest, it will enter the Fast_BFT process. In Fast_BFT, the primary is allowed to handle transactions alone, and the replicas can only receive the messages sent by the primary. The experimental results show that the CF-BFT protocol significantly reduces the communication overhead and improves the throughput and scalability of the consensus protocol. Compared with the SAZyzz protocol, the throughput is increased by 3 times in the best case and 60% in the worst case.