IEEE Access

Quantum Key Distribution Network Simulator With Hyperparameter Tuning for Realistic Performance Analysis

Ju-Bong Kim, Hyun-Kyo Lim, Wonhyuk Lee, Dahyun Yum, Chankyun Lee

Published Jan 1, 2026• 1 citation

Abstract

Realistic simulation of quantum key distribution (QKD) networks requires a combination of precise models of quantum channels and network functions. Unfortunately, existing QKD network simulators lack either rigorous quantum physics modeling or network key-management and routing protocols, which limit their practical applicability. To address this limitation, we propose a QKD network simulator with hyperparameter tuning (QKDSim-HT), a NetSquid-based simulator specialized for polarization-based discrete-variable QKD networks. Specifically, QKDSim-HT models properties in quantum physics (photon loss, polarization-dependent depolarization, detector inefficiencies, dark counts, and dead times) as well as advanced functionalities in networking algorithms (multi-hop key relay and adaptive routing). Extensive simulations over diverse topologies reveal that the networking performance varied with respect to the fundamental properties of quantum physics, such as depolarization, fiber length, and channel attenuation. As a representative use case of QKDSim-HT, simulation results from QKDSim-HT over simple examples clearly manifest that a design of QKD networks highly affects performance of the networks. Accordingly, QKDSim-HT can serve as a practical platform for performance evaluation and optimization of quantum secured network.

DOI: 10.1109/access.2026.3664094

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