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arXiv · 1301.3138

Security of two-way quantum key distribution

Normand J. Beaudry·Marco Lucamarini·Stefano Mancini·Renato Renner
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Abstract

Quantum key distribution protocols typically make use of a one-way quantum channel to distribute a shared secret string to two distant users. However, protocols exploiting a two-way quantum channel have been proposed as an alternative route to the same goal, with the potential advantage of outperforming one-way protocols. Here we provide a strategy to prove security for two-way quantum key distribution protocols against the most general quantum attack possible by an eavesdropper. We utilize an entropic uncertainty relation, and only a few assumptions need to be made about the devices used in the protocol. We also show that a two-way protocol can outperform comparable one-way protocols.

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Normand J. Beaudry, Marco Lucamarini, Stefano Mancini, Renato Renner. 2013-12-12. Security of two-way quantum key distribution. https://doi.org/10.1103/physreva.88.062302

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