Research On Secure Multi-Party Quantum Computation Protocols

Secure multi-party quantum computation,as one of the most popular research directions of quantum cryptography in the past two decades,has many advantages that classical secure multi-party computation cannot achieve.By introducing quantum information technology into the classical multi-party computation protocol,secure multi-party quantum computation can enable two or more participants to jointly calculate a joint function while ensuring the security of their input data.In order to make the protocol suitable for a specific scenario,secure multi-party quantum computation with special properties has developed.Quantum private comparison as a special type of secure multi-party quantum computation has received extensive attention from scholars in recent years due to its wide applicability and easy portability to other complex secure multi-party quantum computation protocols.A quantum private comparison protocol allows two participants to jointly calculate whether their secret data is equal and to keep the secret data of the two participants secret.Under current scientific and technological conditions,it is difficult to obtain quantum resources.As a result,the semi-quantum private comparison protocol was proposed,which can effectively reduce the quantum capability required by the two participants and make the protocol easier to implement in the future.This paper focuses on the related issues of secure multi-party quantum computation and especially semi-quantum private comparison about which we obtain the following two results.1.Two semi-quantum private comparison protocols based on Bell states are analyzed and two types of attack on them are proposed.In the first type of attack,an external eavesdropper can make participants accept a wrong result.In the second type of attack,a malicious participant may obtain the secret information of the honest participant while making the other honest participant accept the incorrect result.In order to resist these two types of attack,an improved semi-quantum private comparison protocol based on Bell states and measure-resend model is proposed.The proposed protocol can also resist some typical types of attack related to semi-quantum cryptography,such as the intercept-resend attack,the measure-resend attack,and the entangle-measure attack.2.The security loophole of the semi-quantum private comparison protocol based on the G-like states is analyzed and a dishonest participant can use the loophole to obtain the secret of another honest participant with certain probability by performing a double CNOT attack.Without increasing the quantum capability of the classical participants,we offer an improved semi-quantum private comparison protocol which can effectively prevent the secret of the honest participant from being stolen and can also resist some well-known attack that the original protocol can prevent.