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arXiv · 2503.21186

DemoQuanDT: A Carrier-Grade QKD Network

P. Horoschenkoff·J. Henrich·R. Böhn·I. Khan·J. Rödiger·M. Gunkel·M. Bauch·J. Benda·P. Bläcker·E. Eichhammer·U. Eismann·G. Frenck·H. Griesser·W. Jontofsohn·N. Kopshoff·S. Röhrich·F. Seidl·N. Schark·E. Sollner·D. von Blanckenburg·A. Heinemann·M. Stiemerling·M. Gärtner
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Abstract

Quantum Key Distribution Networks (QKDN) enable secure communication even in the age of powerful quantum computers. In the hands of a network operator, which can offer its service to many users, the economic viability of a QKDN increases significantly. The highly challenging operator-user relationship in a large-scale network setting demands additional requirements to ensure carrier-grade operation. Addressing this challenge, this work presents a carrier-grade QKDN architecture, which combines the functional QKDN architecture with the operational perspective of a network operator, ultimately enhancing the economic viability of QKDN. The focus is on the network and key management aspects of a QKDN while assuming state-of-the-art commercial QKD-Modules. The presented architecture was rolled out within an in-field demonstrator, connecting the cities of Berlin and Bonn over a link distance of 923 km across Germany. We could show, that the proposed network architecture is feasible, integrable, and scalable making it suitable for deployment in real-world networks. Overall, the presented carrier-grade QKDN architecture promises to serve as a blueprint for network operators providing QKD-based services to their customers.

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P. Horoschenkoff, J. Henrich, R. Böhn, I. Khan, J. Rödiger, M. Gunkel, M. Bauch, J. Benda, P. Bläcker, E. Eichhammer, U. Eismann, G. Frenck, H. Griesser, W. Jontofsohn, N. Kopshoff, S. Röhrich, F. Seidl, N. Schark, E. Sollner, D. von Blanckenburg, A. Heinemann, M. Stiemerling, M. Gärtner. 2025-03-27. DemoQuanDT: A Carrier-Grade QKD Network. https://doi.org/10.1364/jocn.563470

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