量子金鑰分配系統中繼方法之研究

Investigation of Relay in Quantum Key Distribution System

尤佳良(Chia-Liang Yu)

指導教授 ： 郭斯彥

國立臺灣大學/電機資訊學院/電機工程學研究所/碩士(2010年)

https://doi.org/10.6342/NTU.2010.00027

摘要

以現今的祕密通訊系統而言，其安全性是架構在對於對手計算能力上的假設，並非架構在理論上完美的安全。當硬體和演算法變得更快時，這種祕密通訊系統將變得脆弱。要達到完美的安全性，其方法是使用一次性金鑰，然而這表示金鑰必需和資料一樣長而僅僅可被使用一次。金鑰分配在使用一次性金鑰的方法中是一個重要的課題。
由於量子的特性，量子金鑰分配系統具有不需擔心竊聽者而傳送金鑰的能力。然而也由於量子的特性，量子金鑰分配系統沒有所謂的增幅器，這表示它只能在一定的有限距離內傳送金鑰。為了增加金鑰可傳送的距離，量子金鑰分配系統需要有量子金鑰中繼器的幫助。
在這篇論文裡，我們研究量子金鑰中繼器，提議一種使用現有技術的中繼器，並且對三種中繼器模型建立數學模型，來比較及分析他們的可靠性及效能。

關鍵字

量子態 ； 纏結 ； 量子金鑰分配

並列摘要

In modern secure communication system, the security is based on computational security, not perfect security. This kind of secure communication system will become weaker when the hardware and the algorithms become faster. To achieve perfect security, the method is “one time pad”, which means the key should be as long as the data and be used only once. Key distribution is an important issue in “one time pad” method.
Due to the quantum’s property, quantum key distribution (QKD) system has the ability to transmit a key without worrying about the eavesdroppers. However, also due to the quantum’s property, QKD system has no so called “amplifier”, which means it can only transmit a key in a limited distance. In order to enlarge the key distribution distance, QKD system needs the help of QKD relay.
In this thesis, we investigate about QKD relays, propose a relay model with classical technologies, and create mathematical models for three relay models to compare and analyze their reliabilities and performances.

並列關鍵字

Quantum state ； Entanglement ； Quantum key distribution

參考文獻

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