Abstract: Consensus mechanism is the key of block chain technology.In the DPoS consensus mechanism,each node can indepen-dently determine its trusted authorization nodes,and these authorization nodes will take turns to generate new blocks for rapid consensus verification.But DPoS still has security problems such as inactive voting and node corruption.Aiming at these two problems,this paper proposed an improved DPoS scheme based on reward incentive.The evoting rewardr is used to encourage nodes to actively participate in the process of voting and the ereporting rewardr is used to encourage common nodes to report bribery nodes.The Matlab simulation experiments show that the introduction of voting reward improves the voting enthusiasm of nodes.Compared with the original DPoS consensus mechanism,in which the number of voting nodes accounts for 45% to 50%,the introduction of two different voting reward methods increases the number of voting nodes to 65% to 70% and 55% to 60% respectively.Compared with the original DPoS consensus mechanism,in which the proportion of nodes that do not accept bribes will decrease as the bribery of malicious nodes increases,the introduction of the reporting reward method makes the proportion of choosing reporting nodes increase significantly,and the proportion of choosing reporting nodes can increase to 54% when the number of voting rounds is 20.The experiment results show that the improved DPoS mechanism can not only make more nodes vote,but also enhance the bribery resistance of the common nodes,so that the probability of malicious nodes becoming the “trustee” becomes smaller,thus ensuring the security of the network.

Key words: Algorithm improvement, Blockchain, Consensus mechanism, Delegated proof-of-stake, Game theory, Incentive mechanism