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Demonstration of an Active Quantum Key Distribution Network



Xiao Tang, Lijun Ma, Alan Mink, Anastase Nakassis, Hai Xu, Barry J. Hershman, Joshua Bienfang, David H. Su, Ronald Boisvert, Charles W. Clark, Carl J. Williams


We previously demonstrated a high speed, point to point, quantum key distribution (QKD) system with polariztion coding over a fiber link, in which the resulting cryptographic keys were used for one-time pad encryption of real time video signals. In this work, we extend the technology to a three-node active QKD network - one alice and two Bobs. A QKD network allows multiple users to generate and share secure quantum keys. In comparison with a passive QKD network, nodes in an active network can actively select a destination as a communication partner and therefore, its sifted-key rate can remain at a speed almost as high as that in the point-to-point QKD. We demonstrate our three-node QKD network in the context of a QKD secured real-time video surveillance system. In principle, the technologies for the three-node network are extendable to multi-node networks easily. In this paper, we report our experiments, including the techniques for timing alignment and polarization recovery during switching, and discuss the network architecture and its expandability to multi-node networks.
Proceedings Title
Demonstration of an Active Quantum Key Distribution Network
Conference Location


optical switches, quantum communications network, quantum cryptography, quantum key distribution


Tang, X. , Ma, L. , Mink, A. , Nakassis, A. , Xu, H. , Hershman, B. , Bienfang, J. , Su, D. , Boisvert, R. , Clark, C. and Williams, C. (2006), Demonstration of an Active Quantum Key Distribution Network, Demonstration of an Active Quantum Key Distribution Network, , USA, [online], (Accessed May 21, 2024)


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Created July 31, 2006, Updated October 12, 2021