Analysis And Design Of A Secure Multi-party Computation Protocol Based On Game System Theory

In the context of big data,secure multi-party computation solves the privacy problem of data owners in the process of multi-source data analysis and fusion.On the premise that the data is fully utilized,the encryption and privacy of the data are guaranteed.Rational and secure multi-party computing expands the traditional secure multi-party computing,and is a product of the fusion of game theory and secure multiparty computing.The introduction of rational participants makes the secure multi-party computation model more in line with practical significance and practical applications,and the reliability of calculation results is guaranteed through utility function analysis.This thesis combines information theory,game theory and general security theory to study the behavior change trends of participants and adversary selection in secure multiparty computing.The research content includes a rational two-party computing protocol based on security entropy and time-varying adversaries based on entropy.Select model and utility function and time-varying simulation of entropy.The specific work content is as follows:(1)A rational two-party computation protocol based on the criterion of security entropy.Rational and secure two-party computation is one of the important researches in cryptography.Since the purpose of rational participants is to maximize their own utility,in most cases the behavior of participants is a mixed strategy.The Nash equilibrium under the hybrid strategy will cause changes in entropy.Existing protocols have solved the fairness problem of two-party computation under hybrid strategy through entropy function,and solved the security problem of rational two-party computation through utility function.However,the cost of ensuring the security of the protocol by setting a utility function that is too high is often higher than the value of the protocol itself,and the protocol is only applicable to a single scenario.Therefore,this paper proposes a secure two-party computing protocol based on the entropy criterion,and sets the corresponding security entropy threshold according to different scenarios.The security entropy is used as a method to evaluate the security of two parties in different scenarios.At the same time,this paper explores the relationship between security entropy and utility function to ensure that the optimal utility function is set within the range of the security entropy threshold.(2)A time-varying rational adversary optimal selection model based on entropy.In cryptography,secure multi-party computing involves multiple participant entities,each of which has its own secret input and hopes to jointly calculate a function through a certain interactive protocol.In this process,cheating by any party will lead to errors in the final result.In order to prevent participants from cheating,however,existing protocols can only detect and deal with malicious attackers after being attacked.This passive approach will not only consume more resources,but also cause excessive losses for participants.In response to the above problems,this paper proposes an optimal adversary replacement model based on the time-varying nature of entropy.According to the change of time,the security entropy value of the secure multi-party computation model is evaluated.If the entropy value exceeds expectations,some adversaries will be replaced through the reputation mechanism to always ensure the security status of the model.Experiments show that the proposed model can better predict the insecure state of the system,and the security of the model can be guaranteed at all times through adversary selection.At the same time,the efficiency of cryptographic protocol design is improved.(3)Secure electronic bidding protocol based on game system theory.This article will secure multi-party computation protocol based on game theory is applied to electronic bidding in the background,through understanding the background of electronic bidding status quo and existing problems,secure multi-party computation protocol based on game theory are used to improve for privacy in electronic auction protocol,and prevent malicious operation of bidders in the bidding process.