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arXiv:0810.1264 · Optics Express

Field test of a practical secure communication network with decoy-state quantum cryptography

Teng-Yun Chen, Hao Liang, Yang Liu, Wen-Qi Cai, Lei Ju, Wei-Yue Liu, Jian Wang, Hao Yin, Kai Chen, Zeng-Bing Chen, Cheng-Zhi Peng, Jian-Wei Pan

Published Apr 6, 2009• 124 citations
arXivHTMLPDF

Abstract

We present a secure network communication system that operated with decoy-state quantum cryptography in a real-world application scenario. The full key exchange and application protocols were performed in real time among three nodes, in which two adjacent nodes were connected by approximate 20 km of commercial telecom optical fiber. The generated quantum keys were immediately employed and demonstrated for communication applications, including unbreakable real-time voice telephone between any two of the three communication nodes, or a broadcast from one node to the other two nodes by using one-time pad encryption.

DOI
10.1364/oe.17.006540

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