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arXiv · 1203.0628

Extending the Reach of QKD Using Relays

Stephen M. Barnett·Simon J. D. Phoenix
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Abstract

One of the obstacles to deployment of QKD solutions has been the distance limitation. Solutions using relays have been proposed but these rely on link-by-link key establishment. We present a new technique to extend the distance of a quantum key distribution channel using an active relay. Each relay acts as an intercept/resend device and allows the establishment of an end-to-end key. It has been argued that such relays cannot be used to extend the distance, but we show that with a suitable adaptation of the protocol the effective key distribution distance can be increased.

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Stephen M. Barnett, Simon J. D. Phoenix. 2012-03-03. Extending the Reach of QKD Using Relays. https://doi.org/10.1109/ieeegcc.2011.5752492

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