Research On Quantum Token Signature Protocol

Quantum signature is a quantum method to solve the problem of message authentication and achieve the non-repudiation and non-forgery of the signature message.It effectively improves the security of the protocol in the quantum computing environment and is an indispensable part of improving the theoretical system of quantum cryptography.In practice,to solve the problem that signers cannot complete the signature operation under some special circumstances,people put forward the concept of proxy signature,that is,signers designate additional participants to complete the signature process on their behalf.However,it is found that there are some problems in proxy signature protocols such as abuse of signature authority.To solve this problem,people begin to consider the quantum proxy signature protocol which can control the signature permission.On this basis,this paper proposes a quantum proxy signature scheme ——quantum token signature（QTS）.In this paper,the quantum token signature is studied systematically.Built on the in-depth analysis from the perspective of participants,this paper analyzes the security risks and application problems caused by this,puts forward specific improvement strategies,and provides a basic theoretical framework for the modification of signer rights in the quantum token signature protocol.In addition,combining different security requirements and existing security technologies,an adjustable quantum token signature protocol is proposed for the first time,which realizes the purpose of modifying proxy signature permission and solves the corresponding problems existing in existing protocols.On this basis,we also define the scope of activities of agents,and give a specific scheme,so that agents can only sign certain types of files,here require that all files need at least two agents to complete the signing process.Finally,through the security analysis,it is proved that the proposed protocol meets the security requirements such as non-forgery and non-repudiation.In the application of practical quantum token signatures,this paper designs a new proxy voting protocol based on the quantum token signature.In the protocol,voters use the shift operator to assign the ballot information to the quantum token and then give it to the agent,who participates in the monitoring and counting stage,to better protect the privacy of voters.The design of the protocol also adds a publicity stage,in which all voters can verify that their votes have been counted correctly,which not only ensures the anonymity of voter information but also makes the election process more transparent and fair.