【作者】 张静；

【导师】 周艺华；

【作者基本信息】 北京工业大学 ， 计算机科学与技术， 2020， 硕士

【摘要】 量子密钥分发和量子密钥协商是量子密码协议领域非常重要的两个分支,不同于量子密钥分发单向传输,量子密钥协商协议中,密钥由所有的参与者共同决定,并且所有参与者对密钥的贡献相同。这些特性使得量子密钥协商有更高的安全性和公平性。自2004年,周南润提出第一个两方量子密钥协商协议,越来越多的QKA协议被提出,并从双方扩展到多方。但是对大多数QKA的研究都是基于离散变量量子态的,而基于离散变量的QKA协议存在以下弊端:(1)理想的单光子源和单光子探测器实现困难,受探测器噪声影响,存在暗计数问题,尚缺乏高效的单光子探测器;(2)单光子在信道传输中,易受环境噪声干扰,易被吸收,导致传输效率和传输距离受限。与离散变量相比,连续变量协议具有多光子束特性、对噪声的免疫性强、探测器噪声可利用、载体携带密钥比特数高、与现有光纤通信系统兼容性强等优势。本文围绕连续变量量子密钥协商这一热点课题,借助连续变量GHZ态、连续变量双模压缩态、相干态等连续变量量子态,设计了三种基于连续变量量子态的量子密钥协商协议,并对所提出协议进行正确性分析和安全性分析,具体研究内容如下:(1)利用连续变量GHZ态,提出了一种基于第三方的多方量子密钥协商协议,第三方制备连续变量GHZ状态,将输出模分别发送给参与者。参与者依次将自己的密钥通过平移操作进行编码,直到接收到编码了所有参与者密钥信息的量子态为止,参与者计算可得到一个共同的密钥。安全分析表明,提出的QKA协议不仅可以抵抗参与者的攻击,还可以抵抗共谋攻击和分束器攻击。(2)为了解决针对探测器引起的黑客攻击,提出一种基于相干态的测量设备无关的量子密钥协商协议。首先提出两方量子密钥协商协议,然后将其推广到多方。根据PM方案的安全性等价于相应的EB方案,为了方便安全性的分析,我们还描述了对应的EB方案,然后分析了协议的安全性,分析表明,协议可以抵抗个体攻击和集体攻击等攻击。(3)以连续变量双模压缩态为基础,提出了一种受第三方控制的连续变量多方QKA协议。第三方制备连续变量双模压缩态,将一个输出模发送给其中一个参与者。参与者以线性方式依次将自己的密钥进行编码,然后第三方进行纠缠度检测,最后公布诱骗态,参与者去除诱骗态后计算可得到一个共同的密钥。安全分析表明,提出的QKA协议可抵抗中间人攻击和共谋攻击等。更多还原

【Abstract】 Quantum key distribution and quantum key negotiation are two very important branches in the field of quantum cryptography.Unlike the one-way transmission of quantum key distribution,in the quantum key agreement protocol,the key is determined by all participants and jointly,All participants contribute the same to the key.These characteristics make quantum key negotiation have higher security and fairness.Since 2004,Zhou Nanrun proposed the first two-party quantum key agreement protocol,and more and more QKA protocols have been proposed and extended from both parties to multiple parties.However,most of the researches on QKA are based on discrete variable quantum states,and the QKA protocol based on discrete variables has the following disadvantages:(1)The ideal single photon source and single photon detector are difficult to implement,are affected by the detector noise,and have dark counts However,there is still a lack of efficient single-photon detectors.(2)Single-photon transmission in a channel is susceptible to environmental noise and easily absorbed,resulting in limited transmission efficiency and transmission distance.Compared with discrete variables,continuous variable protocols have the advantages of multi-photon beam characteristics,strong immunity to noise,availability of detector noise,high number of key bits carried by the carrier,and strong compatibility with existing optical fiber communication systems.This paper focuses on the hot topic of continuous variable quantum key negotiation.With the help of continuous variable quantum states such as continuous variable GHZ state,continuous variable two-mode squeezed state,and coherent state,three quantum key agreement protocols based on continuous variable quantum state are designed.The correctness analysis and security analysis of the proposed protocol are carried out.The specific research contents are as follows:(1)Using a continuous variable GHZ state,a multi-party quantum key agreement protocol based on a third party is proposed.The third party prepares the continuous variable GHZ state and sends the output modules to the participants.Participants encode their keys in quantum states through translation operations until they receive a quantum states that encodes all participants’ key information.And participants can calculate a common key.Security analysis shows that the proposed QKA protocol can not only resist the attacks of participants,but also resist collusion attacks and beam splitter attacks.(2)In order to solve the hacker attack caused by the detector,a coherentstate-based measurement device-independent quantum key agreement protocol is proposed.First,a two-party quantum key agreement protocol is proposed,and then it is extended to multiple parties.According to the security of the PM scheme is equivalent to the corresponding EB scheme.In order to facilitate the security analysis,we also describe the corresponding EB scheme,and then analyze the security of the protocol.The analysis shows that the protocol can resist common attacks.(3)Based on the continuous variable dual-mode compression state,a continuous variable multi-party QKA protocol controlled by a third party is proposed.A third party prepares a continuous variable two-mode squeezed state and sends an output mode to one of the participants.Participants encode their own keys sequentially in a linear manner,then a third party performs an entanglement detection,finally announces the decoy state,and participates in the combination to remove the deceive state and calculate a common key.Security analysis shows that the proposed QKA protocol can resist man-in-the-middle attacks and collusion attacks.更多还原