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arXiv · 0811.2628

Finite-key analysis for practical implementations of quantum key distribution

Raymond Y. Q. Cai·Valerio Scarani
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Abstract

The lists of bits processed in quantum key distribution are necessarily of finite length. The need for finite-key unconditional security bounds has been recognized long ago, but the theoretical tools have become available only very recently. We provide finite-key unconditional security bounds for two practical implementations of the Bennett-Brassard 1984 coding: prepare-and-measure implementations without decoy states, and entanglement-based implementations. A finite-key bound for prepare-and-measure implementations with decoy states is also derived under a simplified treatment of the statistical fluctuations. The presentation is tailored to allow direct application of the bounds in experiments. Finally, the bounds are also evaluated on a priori reasonable expected values of the observed parameters.

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Raymond Y. Q. Cai, Valerio Scarani. 2009-09-14. Finite-key analysis for practical implementations of quantum key distribution. https://doi.org/10.1088/1367-2630%2F11%2F4%2F045024

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