Investigation of Relay in Quantum Key Distribution System

• Main Authors: Chia-Liang Yu, 尤佳良
• Other Authors: 郭斯彥
• Format: Others
• Language: en_US
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/12620841114133037620

碩士 === 國立臺灣大學 === 電機工程學研究所 === 98 === 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.