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arXiv · 2504.01454

Quantum Key Distribution with Efficient Post-Quantum Cryptography-Secured Trusted Node on a Quantum Network

Yoann Piétri·Pierre-Enguerrand Verdier·Baptiste Lacour·Maxime Gautier·Heming Huang·Thomas Camus·Jean-Sébastien Pegon·Martin Zuber·Jean-Charles Faugère·Matteo Schiavon·Amine Rhouni·Yves Jaouën·Nicolas Fabre·Romain Alléaume·Thomas Rivera·Eleni Diamanti
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Abstract

Quantum Key Distribution (QKD) enables two distant users to exchange a secret key with information-theoretic security, based on the fundamental laws of quantum physics. While it is arguably the most mature application of quantum cryptography, it has inherent limitations in the achievable distance and the scalability to large-scale infrastructures. While the applicability of QKD can be readily increased with the use of intermediary trusted nodes, this adds additional privacy requirements on third parties. In this work, we present an efficient scheme leveraging a trusted node with lower privacy requirements thanks to the use of post-quantum cryptographic techniques, and implement it on a deployed fiber optic quantum communication network in the Paris area.

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Yoann Piétri, Pierre-Enguerrand Verdier, Baptiste Lacour, Maxime Gautier, Heming Huang, Thomas Camus, Jean-Sébastien Pegon, Martin Zuber, Jean-Charles Faugère, Matteo Schiavon, Amine Rhouni, Yves Jaouën, Nicolas Fabre, Romain Alléaume, Thomas Rivera, Eleni Diamanti. 2025-04-02. Quantum Key Distribution with Efficient Post-Quantum Cryptography-Secured Trusted Node on a Quantum Network. https://arxiv.org/abs/2504.01454

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