# Practical issues in decoy-state quantum key distribution based on the central limit theorem. (arXiv:1702.08531v2 [quant-ph] UPDATED)

Decoy-state quantum key distribution is a standard tool for long-distance

quantum communications. An important issue in this field is processing the

decoy-state statistics taking into account statistical fluctuations (or

"finite-key effects"). In this work, we propose and analyze an option for decoy

statistics processing, which is based on the central limit theorem. We discuss

such practical issues as an inclusion of the failure probability of the

decoy-states statistical estimates in the total failure probability of a QKD

protocol and also taking into account the deviations of the binomially

distributed random variables used in the estimations from the Gaussian

distribution. The results of numerical simulations show that the obtained

estimations are quite tight. The proposed technique can be used as a part of

post-processing procedures for industrial quantum key distribution systems.