Blockchain Performance Improvement Scheme Based On Practical Byzantine Fault-Tolerant Consensus Algorithm

With the rise of digital currencies represented by Bitcoin,blockchain as its underlying technology has also received great attention from blockchain industry.The characteristics of decentralization and tamper-proof of blockchain make it widely used in banking and other fields.The consensus algorithm is an important part of the blockchain,which has an important impact on system throughput,transaction confirmation time and other aspects.However,the PBFT consensus algorithm applied to the alliance chain has some defects.For example,the high communication overhead the process of three-phase consensus causes high communication overhead,master nodes are selected in turn according to the serial number,and the nodes cannot join and exit dynamically.In this context,PBFT+ consensus algorithm is proposed in this paper.The main research contents are as follows:(1)Research the current situation of blockchain consensus algorithms at home and abroad,and deeply understand the principles and implementation steps of various blockchain consensus algorithms at home and abroad.Through comparative analysis of the advantages and disadvantages of various consensus algorithms,combined with some mainstream consensus algorithm models and methods,the more practical PBFT consensus algorithm is selected as the main research content of this article.(2)Aiming at the problems of the Practical Byzantine Fault Tolerance(PBFT)consensus algorithm applied to the alliance chain,such as random selection of master nodes,high latency,and inconsistent block height,an improved Practical Byzantine Fault Tolerance(PBFT+)consensus algorithm is proposed.First,PBFT+ algorithm selects the master node based on the credit mechanism,and introduces a credit hierarchy system to evaluate system nodes.Then it selects the node with the highest credit value as the master node,which can ensure the optimality of the master node and avoid frequent view changes through the standby master node mechanism.Secondly,PBFT+ algorithm optimizes the three-phase consensus process.It improves the confirmation message from the whole network node in the confirmation phase to the master node collecting confirmation information,which reduces the communication overhead.Finally,the block height synchronization mechanism ensures that the consensus node block is highly consistent,and a consensus can be reached quickly.The experimental results show that the PBFT+ consensus algorithm effectively reduces the consumption of system resources and reduces the delay.(3)To solve the problem that PBFT algorithm cannot realize dynamic entry and exit of network nodes,a dynamic network consensus mechanism based on PBFT consensus algorithm is proposed in this paper.Combining with the ring signature scheme,the signature and verification process of PBFT consensus algorithm are improved,and a dynamic entry and exit protocol is designed.First of all,new nodes can join the blockchain network and participate in the consensus,which can be achieved without stopping the operation of the nodes in the network.At the same time,the consensus node can exit the blockchain network through the ring signature verification.The experimental results show that the time of node join and exit of PBFT+ algorithm is much lower than that of PBFT algorithm,and the improved PBFT algorithm combined with ring signature can effectively solve the problem of node join and exit.