在量子系統成長的威脅下，目前的加密系統有望在未來受到威脅。BB84協議於西元1984年提出，旨在建立一種新的加密系統，即量子金鑰分發（QKD）。該協議利用量子物理的獨特特性實現了信息理論安全，自1984年起，各方研究不斷推進金鑰生成速率。關於QKD系統的研究始於2012年。在先前的研究中，相干單向（COW）協議QKD具有更高的金鑰生成率，此外，由於後處理模組需要大量的計算和內存資源，如何實現與之整合在同一個系統中的封包處理模組成為了一個問題。

在本論文中，實現了一個用於同調單向協議的可編程物理通道接口。量子通道和經典通道都得到了實現。由於量子位元是通過相位編碼的，因此本文中的可編程時鐘頻率確定了量子位元的發送頻率。量子位元脈衝的發送頻率為312.5 MHz。此外，以在古典通道的1G以太網下進行傳輸的傳輸控制協議，以確保兩側後處理信息傳輸的可靠性，後處理模組到封包處理模組的訊息讀取速率達到3 Gbps。

Under the threat posed by the growth of quantum systems, current cryptographic systems are expected to be vulnerable in the future. The BB84 protocol was introduced in 1984 to establish a new cryptographic system, quantum key distribution (QKD). This protocol leverages the unique characteristics of quantum physics to achieve information-theoretic security, ensuring a continuously improved key generation rate. The research of system level integration of QKD begins from 2012. From those previous works, coherent one-way (COW) protocol QKD has higher key generation rate. Additionally, the integration of packet processing module is a problem. Since the huge computing and memory resource required by post-processing module.

In this thesis, a programmable physical channel interface for the COW protocol is implemented. Both the quantum channel and the classical channel are implemented. As the quantum bit (qubit) is encoded by phase, the repetition frequency of the qubit is determined by the programmable clock frequency in this work. The repetition frequency of the qubit pulse is 312.5 MHz. Additionally, the transmission control protocol (TCP) is implemented for transmission under 1G Ethernet in the classical channel. The message access rate from post-processing module to the packet processing module achieves 3 Gbps. TCP is employed to ensure the reliability of post-processing information transmission between the two sides.

摘要 i
Abstract iii
誌謝 v
1 Introduction 1
1.1 Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.3 Main Contributions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.4 Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2 Background Knowledge and Literature Survey 5
2.1 The Needs for QKD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2 QKD Cryptography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.3 Classical Channel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.4 Related Works . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.4.1 Comments on Related Works . . . . . . . . . . . . . . . . . . . . . . . 14
3 A Programmable Interface Structure for QKD 21
3.1 System Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
3.2 Quantum Channel Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
3.2.1 Overview of Quantum Channel Interface . . . . . . . . . . . . . . . . 23
3.2.2 Structure of Pulse Generator . . . . . . . . . . . . . . . . . . . . . . . 27
3.3 Classical Channel Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
3.3.1 Overview of Classical Channel . . . . . . . . . . . . . . . . . . . . . . 34
3.3.2 Structure of networkCentCtrl . . . . . . . . . . . . . . . . . . . . . . . 38
4 Implementation Results 49
4.1 Experimental Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
4.1.1 Quantum Channel . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
4.1.2 Classical Channel of Transmitting Path . . . . . . . . . . . . . . . . . 50
4.1.3 Classical Channel of Receiving Path . . . . . . . . . . . . . . . . . . . 55
4.1.4 Summary of Delay in Classical Channel . . . . . . . . . . . . . . . . . 56
4.2 Utilization of Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
4.3 Evaluation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
4.3.1 Quantum Channel . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
4.3.2 Classical Channel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
4.3.3 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
vii
5 Conclusion and Future Work 65
5.1 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
5.2 Future Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
References 67

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