Design And Implementation Of The Blockchain Oracle Based On Distributed Trust Models

In recent years,with the vigorous development of blockchain technology,more and more scenarios and applications need to obtain data in the physical world.Since the blockchain system is closed and cannot accept uncertain data input,and the unreliability of off-chain data is high,the security and consistency of the obtained data cannot be guaranteed.Therefore,the blockchain oracle machine,as the middleware of the blockchain technology ecology,assumes the key role of transmitting offchain data to the on-chain.Therefore,the research on blockchain oracles has also been valued by people,and it is meaningful and valuable to study credible oracle solutions to ensure the security of data transmission.Firstly,this paper investigates and analyzes the incentive mechanism of the existing scheme of the blockchain oracle machine,and designs a reward mechanism for centralized reporting based on time priority.By setting two layers of collections in the process of data consensus of the oracle machine,the default layer and the The adjudication layer implements confiscation of funds for potential malicious nodes and implements super-linear rewards for reporting nodes to achieve incentive compatibility between the system and individuals.Then this paper uses the idea and method of evolutionary game to build a game model for this incentive mechanism,calculate the average expected return of the participants,establish a replication dynamic equation group and obtain the evolutionary equilibrium point,and analyze in detail the oracle participating in the consensus by setting different parameters In the decision-making process under different roles,a consistent evolutionary stable strategy is obtained,which proves the correctness of the design of the incentive mechanism.Then,this paper takes reputation as the entry point,studies and designs a trust model for distributed oracles.The reputation value is used as an intuitive indicator to judge the historical behavior of the oracle node,and can also provide a basis for the division of the oracle set in the incentive mechanism set above.By observing the specific behavior of the prophet node participating in the consensus,including the feedback time of the node providing effective data during the data chaining process,the positive degree of participating in the consensus,the evil situation and the influence of historical reputation,the reputation score of the prophet is scored,and the reputation value is updated regularly.In addition to positive reputation incentives,this paper also sets up an incentive-compatible reputation punishment mechanism,so that the higher the reputation value of the participants,the higher the cost of evil,the greater the reputation punishment.Finally,the intelligent contract is used to analyze the prophet scheme proposed in this paper.The test results of transmission cost and verification cost show that the scheme meets certain practical requirements.The test results of reputation experiment prove the feasibility and correctness of the reputation evaluation mechanism design of this scheme.