【作者】 陈莹；

【导师】 胡和平；

【作者基本信息】 华中科技大学 ， 计算机应用技术， 2009， 硕士

【摘要】 量子密码学是基于量子力学原理的,具有无条件安全的新型密码体制。其起源及核心技术是量子密钥分配协议,致力于解决无条件安全密钥分发问题,与一次一密相结合实现无条件安全密码通信。在具备量子力学、量子线路模型及信息论知识基础上,全面了解量子密钥分配协议的研究现状,针对BB84量子密钥分配协议进行深入研究。首先,理论分析BB84协议原理与流程,后处理技术以及可能的攻击方法。然后,基于QCircuit软件对BB84协议及截取/重发攻击方法进行量子线路模型仿真,并结合信息论知识,构造协议可靠性和有效互信息量的量化分析线路模型,定量分析不同攻击模型与噪声信道模型下BB84协议的有效性及安全性。实验分析结果表明:在非理想环境下,BB84协议不进行有效的协商纠错和保密增强,通信双方无法得到一致的安全的共享密钥。因此,进一步仿真分析协商纠错和保密增强后处理协议,在QuCrypto基础上开发仿真软件,初步实现BB84协议结合Cascade协商纠错和Toeplitz矩阵universal2 class H3保密增强的无条件完全密码通信系统的仿真测试,并依据实验结果分析后处理协议在不同误码率下的影响。更多还原

【Abstract】 Quantum cryptography is a new unconditional security cryptography based on the principles of quantum mechanics. Its original and core technology is quantum key distribution protocol(QKD), which is applied to resolve the unconditionally secure key distribution problem, together with one-time pad to achieve the unconditionally secure cryptographical communications.With the knowledge base of quantum mechanics, quantum circuit model and the information theory, the currental research status of quantum cryptographic protocol is knowed comprehensively, and then the BB84 quantum key distribution protocol is studied in details. First of all, the principle and process of BB84 protocol and post processing technology are discussed deeply, as well as its possible attack. Then, based on QCircuit software, the quantum circuit models of simulating BB84 and intercept/resend attacks are designed. Also, together with information theory, the quantitative analysis circuits of the protocol reliability and available mutual information are constructed to analyze the BB84 effectiveness and security under different attacks and channel models. The experimental result shows that, without the effective reconciliation and privacy amplification, the two parties under BB84 protocol can’t share the same and secure key in the non-ideal circumstances.Therefore, the further simulation and analysis of the post-processing protocols containing reconciliation and privacy amplification is carried on. The simulation software is developed based on its former QuCrypto. And the unconditional secure cryptographical communication under the BB84 protocol together with the Cascade reconciliation and Toeplitz matrix universal2 class H3 privacy amplification has been realized. What’s more, we do some experiments on different error rates to analyze the post-processing protocols.更多还原