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Optical Fiber Communication Conference

Madrid Quantum Communication Infrastructure: a testbed for assessing QKD technologies into real production networks

Diego R. Lopez, Juan P. Brito, Antonio Pastor, Vicente Martín, César Sánchez, David Rincón, Vı́ctor López

Published Jan 1, 2021• 14 citations
Publisher

Abstract

We report on the Madrid Quantum Communication Infrastructure, which demonstrates that a telecommunications network can also host quantum communications in a unified, logical and physical infrastructure. Using new Quantum Key Distribution systems paired with modern networking paradigms, we demonstrate a high technology readiness level of QKD installing the network in production facilities and running relevant use cases.

DOI
10.1364/ofc.2021.th2a.4

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We report on the Madrid Quantum Communication Infrastructure, which demonstrates that a telecommunications network can also host quantum communications in a unified, logical and physical infrastructure. Using new Quantum Key Distribution systems paired with modern networking paradigms, we demonstrate a high technology readiness level of QKD installing the network in production facilities and running relevant use cases.
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Abstract Current quantum key distribution (QKD) networks focus almost exclusively on transporting secret keys at the highest possible rate. Consequently, they are built as mostly fixed, ad hoc, logically, and physically isolated infrastructures designed to avoid any penalty to the quantum channel. This architecture is neither scalable nor cost-effective and future, real-world deployments will differ considerably. The structure of the MadQCI QKD network presented here is based on disaggregated components and modern paradigms especially designed for flexibility, upgradability, and facilitating the integration of QKD in the security and telecommunications-networks ecosystem. These underlying ideas have been tested by deploying many QKD systems from several manufacturers in a real-world, multi-tenant telecommunications network, installed in production facilities and sharing the infrastructure with commercial traffic. Different technologies have been used in different links to address the variety of situations and needs that arise in real networks, exploring a wide range of possibilities. Finally, a set of realistic use cases has been implemented to demonstrate the validity and performance of the network. The testing took place during a period close to three years, where most of the nodes were continuously active.
The integration of quantum physics into telecommunications is revolutionizing secure communication, data transmission speed, and network architectures. By leveraging quantum principles such as superposition and entanglement, technologies like Quantum Key Distribution (QKD) and quantum repeaters are enabling unbreakable encryption and long-distance quantum communication. This article explores the applications of quantum phenomena in modern telecommunications infrastructure, highlights key developments in quantum networking, and evaluates their impact on the future of global communication systems.