在近年來量子計算的發展下，傳統加密方法已被證實存在被破譯的風險。為了因應量子計算帶來的挑戰，量子密鑰分發（quantum key distribution, QKD）基於量子物理特性，提供一種全新的安全加密方法。 QKD 系統通過量子訊號進行加密，其中的後處理需要使用大量的計算和內存資源，並使用安全的古典通道進行訊息傳輸，最終生成安全的量子密鑰。
該系統包括三個主要組成部分：量子位檢測協議（篩選）、錯誤更正和隱私放大。本論文中的系統通訊由一條古典通道完成，該通道利用網際網路協定第四版完成傳輸控制協定（TCP）並且以 1 G 乙太網實現。為了確保古典通道的安全性，系統將所有透過古典通道傳輸的訊息輸入雜湊模組（hashing module）以生成獨特的標籤進行驗證。
本論文介紹了一種基於相干單向（coherent one-way, COW）協議的量子密鑰分發（QKD）系統，並實現於 AMD Kintex UltraScale+ FPGA KCU116 Evaluation Kit FPGA 板上。該系統在理論上可達到每秒 5.6 Mbps 的最大密鑰生成速率，並支持高達每秒 18.71 Mbps 的古典通道傳輸速率。此外，通過基於 FPGA 的實現，對實際吞吐量進行了評估。本研究證明了 FPGA 技術有效提升 QKD 系統性能和可靠性。

In recent years, with the advancement of quantum computing, traditional en-cryption methods have been proven to be at risk of being compromised. To address the challenges posed by quantum computing, quantum key distribution (QKD) of-fers a new secure encryption method based on the principles of quantum physics. QKD system received quantum signals for encryption, the encryption required the authenticated channel to generate secure quantum keys.
The QKD system comprises three main components: quantum bit detection agreement (sifting), error correction, and privacy amplification. In this thesis, the communication between these components is facilitated by a classical chan-nel that utilizes the transmission control protocol (TCP) over Internet protocol ver-sion 4 (IPv4). This channel operates with a 1 G small form-factor pluggable (SFP) transceiver. Acknowledgment mechanisms are integrated into the TCP framework to guarantee reliable data exchange, while a hashing module generates unique au-thentication tags to secure the classical channel.
This thesis presents a quantum key distribution (QKD) system based on the coherent one-way (COW) protocol, implemented on the AMD Kintex UltraScale+ FPGA KCU116 Evaluation Kit. The system achieves a theoretical peak secret key generation rate of 5.6,Mbps and supports classical channel transmission rates of up to 18.71,Mbps. The practical throughput is also evaluated through an FPGA-based implementation. This work demonstrates the effectiveness of FPGA technology in enhancing the performance and reliability of QKD systems.

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