Research On Consortium Blockchain Consensus Algorithm Based On Multi-index

Blockchain technology is being widely used in various fields of social life because of its decentralization,safety,and reliability.As the underlying key technology to ensure the consensus of each node’s behavior in the blockchain system,the performance of the consensus algorithm directly affects the operational efficiency of the blockchain system.When the number of nodes in the consensus network increases,the amount of communication between each node will also increase,resulting in a decrease in the system’s efficiency.To improve the operation efficiency of the consortium blockchain system,this thesis studies and improves the operation mechanism of the practical Byzantine fault-tolerant algorithm.The main research contents and innovations are as follows:1.Aiming at the existing consensus algorithms that do not consider the impact of the differences in the performance of the nodes on the consensus efficiency,this thesis designs a model for evaluating the service quality of nodes based on the indicators of nodes.First,collect the indicators of each node through the peer-to-peer network,and use the improved distance method to evaluate the quality of service priority of the node to solve the problem that the node priority cannot be reasonably judged due to the equal value when calculating the similarity between the node and the ideal solution.Then,the priority of the malicious nodes with the top performance is reduced by adjusting the node loyalty weight,thereby reducing the probability of affecting the operational efficiency of the blockchain system.2.Aiming at the problem that the simple selection of primary node and easy generation of network storms in the practical Byzantine fault-tolerant algorithm,this thesis improves it based on the priority list of node service quality.First,the nodes are divided into a set of consistent nodes and a set of standby nodes.The process of node negotiation only requires the participation of nodes in the set of consistent nodes,and the primary node is only generated from the set of consistent nodes.Then,combined with the multi-signature algorithm,the three-phase protocol and the view change protocol are optimized to reduce the communication volume between nodes.Besides,this thesis introduces a node loyalty reward and punishment mechanism and a node state detection mechanism to increase the cost of the node doing evil in the system.Finally,through simulation experiments,comparing the improved scheme with the practical Byzantine fault-tolerant algorithm,we can see that the proposed scheme in this thesis significantly reduces the amount of node communication required in the consensus process compared to the original scheme and has a significant improvement in throughput.The number of malicious nodes in the set of running consistency nodes decreases and eventually levels off.