Analysis And Research Of Blockchain Consensus Algorithm Based On Ethereum

With the development of various encryption currencies such as Bitcoin and application technology,blockchain has attracted more and more attention in many fields.As a distributed accounting system,a key problem of blockchain is how to ensure agreement between distrustful nodes.As an important component of blockchain,consensus algorithm can solve the consistency problem,and its efficiency will directly determine the performance of blockchain system.DPoS consensus algorithm is easier to optimize to meet the requirements of commercial application environment due to its relatively high consensus efficiency,thus has practical application value and good development prospects.Nevertheless,in the existing DPoS consensus algorithms,the mechanism that witness nodes alternately generating blocks puts blockchain systems some threats,such as collusion attack,inactive node voting,and the election process without considering node preference.Therefore,in order to solve the disadvantages existing in the current consensus algorithm based on Ethereum,this paper will combine cryptography and other related technologies to find solutions and optimize the DPoS consensus algorithm for different threats.This paper mainly includes the following two aspects:(1)To solve the problem that witness nodes are easy to collude with each oth er in DPoS consensus algorithm,a delegated proof of stake consensus algorithm with dynamic trust(DT-DPoS)is proposed.The algorithm calculates the trust value of node by designing the trust model,which can effectively measure the trust degree of each node.In the election witness node phase,in order to improve the reliability of the election node,an evaluation criterion based on stake voting and trust value is constructed.At the same time,due to the relatively fixed list of witness nodes,a ring signature scheme is designed in the consensus phase,which improves the privacy and unconditional anonymity of witness nodes.Through theoretical analysis and experimental results,the algorithm reduces the probability of unreliable nodes being elected as witness nodes,improves the reliability and privacy of witness nodes.Thus,the risk of collusion attack is reduced and the security of blockchain system is further improved.(2)To solve the problem that the node voting is not active and the election deviates from the reality in DPoS consensus algorithm,a delegated proof of stake consensus algorithm with reward and punishment mechanism and node preference(RPMNP-DPoS)is proposed.The algorithm divides the state of nodes by designing a reputation mechanism,so that it can be elected for the candidate nodes in combination with the voting values,which will encourage the nodes to expect themselves to have a higher reputation value.According to the generating block behavior and voting behavior of node,a role-based reward and punishment mechanism is designed,so as to encourage the node to actively participate in voting and generating effective block.At the same time,in the election witness node phase,Borda count is used to select the witness nodes which are more in line with the preference of voting nodes,which will be more in line with the actual election situation.Through theoretical analysis and experimental results,the algorithm can take into account the preference selection of nodes,and can quickly eliminate exception nodes,motivate nodes to effectively generate block and vote,thus ensuring the interests of nodes and blockchain systems.