基于信誉投票的PBFT改进方案

Improved PBFT Scheme Based on Reputation Voting

区块链作为一种去中心化、防篡改的分布式账本,其性能从根本上受共识机制效率的影响。实用拜占庭容错算法以视图切换随机选取主节点的方式会导致安全问题,且在节点较多时共识效率变低。针对这两个问题,提出了基于信誉投票的PBFT改进方案。根据节点划分机制评估节点的可靠性,动态地选取高信誉值节点来参与共识,降低恶意节点成为共识节点的概率,增加系统的安全性;根据节点状态转移机制转换节点的角色,维持系统的正确运行,提高系统的稳定性。将所提方案与PBFT方案进行对比实验的结果表明:在系统长期运行中,所提方案能减少共识过程中的拜占庭节点和通信开销,提高容错率和吞吐量。

As a decentralized,tamper-proof distributed ledger,the performance of blockchain is fundamentally affected by the efficiency of consensus mechanisms.Practical Byzantine fault tolerance(PBFT)algorithm randomly selects master nodes through view-switching,leading to problems of security vulnerabilities and low consensus efficiency in the case of large number of nodes.In response to the two problems,a PBFT improvement scheme based on reputation voting is proposed.The reliability of nodes is evaluated according to node division mechanism,where high reputation nodes are dynamically selected to participate in the consensus,and a malicious node is assigned with lower probability of becoming a consensus node,accordingly increasing the security of the system.By switching the role of nodes according to node state transfer mechanism,the scheme can maintain the correct operation of the system and improve the stability of the system.Experiments on the proposed and the traditional PBFT schemes show that the proposed one can reduce Byzantine nodes and communication overhead in long-term consensus processes,and improve the fault tolerance rate and the data throughput of transaction.