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arXiv:1103.3566 · Optics Express

Field test of quantum key distribution in the Tokyo QKD Network

M. Sasaki, Mikio Fujiwara, Hirokazu Ishizuka, Werner Klaus, Kentaro Wakui, Masahiro Takeoka, Shigehito Miki, T. Yamashita, Z. Wang, Akihiro Tanaka, K. Yoshino, Y. Nambu, Satoshi Takahashi, A. Tajima, Akihisa Tomita, T. Domeki, T. Hasegawa, Y. Sakai, Hiroshi Kobayashi, T. Asai, 克宏清水, Toshiyuki Tokura, Toyohiro Tsurumaru, M. Matsui, Toshimori Honjo, Kiyoshi Tamaki, Hiroki Takesue, 康弘都倉, J. F. Dynes, A. R. Dixon, A. W. Sharpe, Zhiliang L. Yuan, A. J. Shields, Shuichi Uchikoga, Matthieu Legré, Samuel Robyr, Patrick Trinkler, Laurent Monat, Jean-Benoît Page, G. Ribordy, Andreas Poppe, A. Allacher, Oliver Maurhart, T. Länger, Momtchil Peev, Anton Zeilinger

Published May 11, 2011• 1,173 citations

Abstract

A secure communication network with quantum key distribution in a metropolitan area is reported. Six different QKD systems are integrated into a mesh-type network. GHz-clocked QKD links enable us to demonstrate the world-first secure TV conferencing over a distance of 45km. The network includes a commercial QKD product for long-term stable operation, and application interface to secure mobile phones. Detection of an eavesdropper, rerouting into a secure path, and key relay via trusted nodes are demonstrated in this network.

DOI: 10.1364/oe.19.010387

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