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arXiv · 1105.5574

QKD with finite resources: secret key rates via Rényi entropies

Silvestre Abruzzo·Hermann Kampermann·Markus Mertz·Dagmar Bruß
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Abstract

A realistic Quantum Key Distribution (QKD) protocol necessarily deals with finite resources, such as the number of signals exchanged by the two parties. We derive a bound on the secret key rate which is expressed as an optimization problem over Rényi entropies. Under the assumption of collective attacks by an eavesdropper, a computable estimate of our bound for the six-state protocol is provided. This bound leads to improved key rates in comparison to previous results.

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Silvestre Abruzzo, Hermann Kampermann, Markus Mertz, Dagmar Bruß. 2011-05-27. QKD with finite resources: secret key rates via Rényi entropies. https://doi.org/10.1103/physreva.84.032321

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