Research And Design Of Game Model For Rational And Secure Computin

As a new research field,rational cryptography has opened up a new research idea for traditional cryptographic protocols.The biggest difference between rational cryptography and traditional cryptography is that the participants in rational cryptography choose their strategies to maximize their own utility.Therefore,it is of wider practical significance to introduce rational participants to construct rational cryptographic protocols based on the idea of game theory.This paper combines game theory,information theory and general security theory to study the strategy choice and utility of participants in the protocol.Our main contributions are as follows.(1)A rational delegating computation scheme based on smart contract.The delegating computation has become an irreversible trend,together comes the pressing need for fairness and efficiency issues.To solve this problem,we leverage game theory to propose a smart contract-based solution.First,according to the behavioral preferences of the participants,we design an incentive contract to describe the motivation of the participants.Next,to satisfy the fairness of the rational delegating computation,we propose a delegating computation protocol based on the smart contract.Specifically,rational participants are to gain the maximum utility and reach the Nash equilibrium in the protocol.Besides,we design a reputation mechanism with a reputation certificate,which measures the reputation from multiple dimensions.And the reputation is used to assure the client’s trust in the computing party to improve the efficiency of the protocol.(2)A rational secure two-party computation protocol based on direction entropy.Rational secure multi-party computation means two or more rational parties to complete a function on private inputs.Unfortunately,the rational parties choose strategies to maximize utility,which will cause players to maliciously execute the protocol and undermine the fairness of the protocol.Existing works on achieving fairness by specific utility functions.In this paper,however,we leverage game theory to propose the direction entropy-based solution.To this end,we utilize the direction vector of the direction entropy to examine the player’s strategy uncertainty and quantify its strategy from different dimensions.Then,we provide mutual information to construct a new utility for the players.What’s more,we measure the mutual information of players to appraise their strategies.By analyzing and proofing of protocol,we can solve the fairness of the protocol.Compared to the previous approaches,our protocol is not required deposits and design-specific utility functions.Furthermore,we conduct simulations using mutual information to construct utility,and the results show that the probability of player honesty is proportional to utility.(3)The attack-defense game scheme for secret sharing.To solve the problem that secrets are intercepted by attackers in the process of secret sharing,we combine game theory and information theory to propose an attack-defense game model for secret sharing.First,we establish an attack-defense channel from the perspective of attackers and defenders.Then,we use the idea of channel capacity to describe the capability limits of both attackers and defenders.Next,we analyze the attack and defense strategies of both attackers and defenders,and find the solution that maximizes the attacker’s gain function and minimizes the defender’s loss function to propose the best attack and defense strategy for both attackers and defenders.Finally,we analyze the influence of the k value on the offensive and defensive capabilities of both the offensive and defensive according to the changing trend of the offensive and defensive capabilities of the offensive and defensive parties.