Improved Practical Byzantine Fault Tolerance Algorithm And Its Application

With the popularity of encrypted digital currency represented by bitcoin,blockchain technology has attracted great attention from industry and academia.Through the application of traditional computer technologies such as distributed storage technology,peer-to-peer network,consensus algorithm,cryptography technology and intelligent contract,blockchain has the characteristics of decentralization,trust,tamper-proofing,openness and transparency.Blockchain is essentially a tamper-proofing account book maintained by many untrusted nodes in a distributed environment.Since nodes are not trusted,the blockchain ensures the consistency of distributed ledger through consensus algorithm.Consensus algorithm is the core supporting the blockchain system,and has an important imp act on the transaction throughput,communication overhead and application scenarios of the system.Practical Byzantine fault tolerance algorithm reduces the complexity of Byzantine fault-tolerant algorithm from exponential level to polynomial level for the first time,and the transaction throughput is high,and the consensus transaction is confirmed,so as to solve the distributed consistency problem in Byzantine mode with less overhead.However,the three-stage consensus broadcasting mechanism of pbft algorithm has the problems of high communication complexity and serious delay.This paper proposes two-way Byzantine fault tolerance(tbft),and studies the coal mine hidden danger information sharing based on tbft algorithm and other blockchain technologies.The main contents are as follows:(1)Based on the practical Byzantine fault-tolerant algorithm,a twice submitted Byzantine fault tolerant consensus algorithm tbft is proposed.Tbft gives the request two opportunities,and messaging abandons the way of pairwise interaction.The algorithm redesigns the three sub protocols and transfers the cost of the third stage in the agreement protocol to the view change protocol and the check point protocol.In the case of mild conflict,four messages reply to the client after delay,which shortens the waiting time of the client;In case of severe conflict,the replica node actively seeks proof from the replicas.If a replica responds and passes the verification,the replica will continue the consensus process;This two-way commit mechanism avoids frequent execution of expensive view change protocols.Experiments show that the two-way Byzantine consensus algorithm proposed in this paper reduces the communication complexity,shortens the waiting time of the client and improves the throughput of the system.(2)Due to the lack of a safe and reliable hidden danger data sharing environment,hidden danger data is stored and controlled by various coal mining enterprises,forming a data island,resulting in the failure to give full play to the safety value of hidden danger data.In view of this situation,this paper designs a coal mine hidden danger data sharing chain based on tbft and other blockchain technologies.Firstly,the alliance chain of semi distributed P2P network mode is constructed.Considering the reality of local storage of coal mine hidden danger information knowledge base,the sharing mode of local storage of original information,information summary and information key content chain is designed;Secondly,the transaction structure of coal mine hidden danger data is designed,and on this basis,the smart contract is constructed to complete the business function of the scheme.Finally,based on this scheme,the blocking time and transaction throughput of tbft consensus algorithm are tested.The test results show that the algorithm has good performance and stability in the simulation scenario.Figure[20]Table[8]Reference[72]...