Research On Blockchain Consensus For Trusted Online Cloud Services

With the development of sharing economy,online cloud service has become one of the popular ways of Internet service.However,the online cloud service builds on virtual environment,the identities of online cloud service members are extremely complex,the system can not identify malicious nodes automatically,and it is difficult to preserve the evidence of malicious behaviors,and followed by upholding accountability is even more difficult.Online cloud service system lacks a set of mechanisms that can improve the access threshold of participants and carry out incentive and accountability.Blockchain is regarded as a very promising alternative to solve the puzzle problem,because blockchain has good characteristics of detrust,decentralization and the traceability.Making trustless of blockchain incorporate the crowdsourcing system,the major challenge is design a reasonable blockchain consensus.This consensus can come to an agreement on credibility of every participate member automatically,prevent trade evidence from tampering,trace malicious behaviors.Given this,this paper is oriented toward online cloud service areas,taking the representative crowdsourcing in the service mode as a typical example,based on the blockchain underlying technology,put forward an innovative credibility certification consensus mechanism of proof-of-trust.Firstly,the subjective logic reputation algorithm is used to calculate the node reputation value,and the reputation value is divided according to the node function.The nodes with high credibility are selected to participate in the consensus,which improves the access requirements of participating nodes.Nodes that satisfied certain conditions would then have the chance to generate blocks,participate in verification,and claim crowdsourcing task.Second,this mechanism uses the unpredictable of time stamp and signature further optimized the choice of the generate block node.In addition,in order to solve the collusion security problem between verification nodes in consensus process,this paper proposes an incentive mechanism framework based on the consensus verification process.By setting a reasonable pricing strategy,the guide nodes tend to give honest verification results,rather than participate in the collusion of malicious nodes.The game theory is used to evaluate the incentive mechanism for the first time,and the impact of irrational nodes in the actual situation is analyzed.The theory analysis and simulation results demonstrate that this paper presents method that can guarantee credibility of candidate nodes,optimize interactive environment,and make honest verification the best strategic of each node.