Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Optics Express

Perspectives and limitations of QKD integration in metropolitan area networks

Slaviša Aleksić, Florian Hipp, Dominic Winkler, Andreas Poppe, Bernhard Schrenk, Gerald Franzl

Published Apr 14, 2015• 63 citations
Publisher

Abstract

Quantum key distribution (QKD) systems have already reached a reasonable level of maturity. However, a smooth integration and a wide adoption of commercial QKD systems in metropolitan area networks has still remained challenging because of technical and economical obstacles. Mainly the need for dedicated fibers and the strong dependence of the secret key rate on both loss budget and background noise in the quantum channel hinder a practical, flexible and robust implementation of QKD in current and next-generation optical metro networks. In this paper, we discuss these obstacles and present approaches to share existing fiber infrastructures among quantum and classical channels. Particularly, a proposal for a smooth integration of QKD in optical metro networks, which implies removing spurious background photons caused by optical transmitters, amplifiers and nonlinear effects in fibers, is presented and discussed. We determine and characterize impairments on quantum channels caused by many classical telecom channels at practically used power levels coexisting within the same fiber. Extensive experimental results are presented and indicate that a practical integration of QKD in conventional optical metro networks is possible.

DOI
10.1364/oe.23.010359

Related papers

Towards a smooth integration of quantum key distribution in metro networks

Slaviša Aleksić, Dominic Winkler, Florian Hipp +3 more

Quantum key distribution (QKD) systems have already reached a reasonable level of maturity. However, a smooth integration of commercial QKD systems in metropolitan area networks has still remained challenging because of technical and economical obstacles. Mainly the need for dedicated fibers and the strong dependence of the secret key rate on both loss budget and background noise in the quantum channel hinder a practical, flexible and robust implementation of QKD in current and next-generation optical metro networks. In this paper, we discuss these obstacles and present approaches to share existing fiber infrastructures among quantum and classical channels. Particularly, a proposal for a smooth integration of QKD in optical metro networks, which implies removing spurious background photons caused by lasers, amplifiers and nonlinear effects in optical fibers, is presented and discussed.

International Conference on Transparent Optical Networks•Jul 1, 2014•14 citations

Impairment Evaluation toward QKD Integration in a Conventional 20-Channel Metro Network

Slaviša Aleksić, Florian Hipp, Dominic Winkler +3 more

Integration of QKD in telecom infrastructures raises noise issues not present in systems using dedicated fibers. Experiments on a 3-node metro network indicate that integration is possible when allocating broadband quantum channels in the O-band.

Optical Fiber Communication Conference•Jan 1, 2015•5 citations

Integrating QKD in telecommunication networks

Vicente Martín Ayuso, Daniel Lancho Lancho, Jesús Martínez-Mateo +2 more

To date, QKD development has mostly focused in non-shared point-to-point links. Despite its limitations, this is the only technology commercially available today, and this makes it even more expensive and not easily deployable. The integration of QKD with the commercial network infrastructure would open the possibility of a scalable deployment and without requiring a massive initial investment QKD could reach a broader market. Current metro area networks are evolving towards optical, passive infrastructures and this opens up a good window of opportunity for QKD integration, since an all-optical clear path among two points in the network is no longer unfeasible or extremely expensive. However, the simultaneous propagation of quantum and classical signals over a shared link poses important problems due to the spilling of photons coming from classical signals. In this talk I’ll present current architectures for all optical metro networks and discuss our results in the integration of QKD in commercial networks

•Jan 1, 2010•1 citation

Quantum communications over optical fiber networks

Thomas E. Chapuran, Robert J. Runser, P. Toliver +13 more

Quantum communications is an emerging field with many promising applications. Its usefulness and range of applicability in optical fiber will depend strongly on the extent to which quantum channels can be reliably transported over transparent reconfigurable optical networks, rather than being limited to dedicated point-to-point links. This presents a number of challenges, particularly when single-photon quantum and much higher power classical optical signals are combined onto a single physical infrastructure to take advantage of telecom networks built to carry conventional traffic. In this paper, we report on experimental demonstrations of successful quantum key distribution (QKD) in this complex environment, and on measurements of physical-layer impairments, including Raman scattering from classical optical channels, which can limit QKD performance. We then extend the analysis using analytical models incorporating impairments, to investigate QKD performance while multiplexed with conventional data channels at other wavelengths. Finally, we discuss the implications of these results for evaluating the most promising domains of use for QKD in real-world optical networks.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Sep 11, 2007•3 citations

Compatibility of quantum key distribution with optical networking

Thomas E. Chapuran, P. Toliver, Robert J. Runser +13 more

Quantum key distribution (QKD) is an emerging technology for secure distribution of keys between users linked by free-space or fiber optic transmission facilities. QKD has usually been designed for and operated over dedicated point-to-point links. However, the commercial world has been developing increasingly sophisticated fiber networks, with basic networking functions such as routing and multiplexing performed in the optical domain. One of the most important practical questions for the future of QKD is to what extent it can benefit from these trends, either to expand the capabilities of dedicated quantum networks, or to avoid the need for dedicated networks by combining quantum and conventional optical signals onto a single infrastructure. In this paper, we report on systematic investigations of these issues using a 1310-nm weak-coherent, phase-encoded B92 prototype QKD system developed by Los Alamos that includes the implementation of error correction, privacy amplification, and authentication. We have demonstrated reconfigurability of QKD networks via optical switching and successful QKD operation in the presence of amplified DWDM signals over 10 km of fiber. We have identified anti-Stokes Raman scattering of the DWDM signals in the fiber as a dominant transmission impairment for QKD, and developed filtering architectures to extend transmission distances to at least 25 km. We have also measured noise backgrounds and polarization variations in network fibers to understand applicability to real-world networks. We will discuss the implications of our results for the choice of QKD wavelengths, wavelength-spacing between QKD and conventional channels, and QKD network architectures.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•May 25, 2005•4 citations

Integration of Quantum Key Distribution in Metropolitan Area Networks

Andreas Poppe, Bernhard Schrenk, Florian Hipp +5 more

The deployment of Quantum Key Distribution forces the development of QKD-links to be operated in current and next-generation photonic metro-access networks. These highly heterogeneous architectures determine the conditions QKD-links need to be optimized for.

Research in Optical Sciences•Jan 1, 2014•6 citations
Quantum key distribution (QKD) systems have already reached a reasonable level of maturity. However, a smooth integration and a wide adoption of commercial QKD systems in metropolitan area networks has still remained challenging because of technical and economical obstacles. Mainly the need for dedicated fibers and the strong dependence of the secret key rate on both loss budget and background noise in the quantum channel hinder a practical, flexible and robust implementation of QKD in current and next-generation optical metro networks. In this paper, we discuss these obstacles and present approaches to share existing fiber infrastructures among quantum and classical channels. Particularly, a proposal for a smooth integration of QKD in optical metro networks, which implies removing spurious background photons caused by optical transmitters, amplifiers and nonlinear effects in fibers, is presented and discussed. We determine and characterize impairments on quantum channels caused by many classical telecom channels at practically used power levels coexisting within the same fiber. Extensive experimental results are presented and indicate that a practical integration of QKD in conventional optical metro networks is possible.
Quantum key distribution (QKD) systems have already reached a reasonable level of maturity. However, a smooth integration of commercial QKD systems in metropolitan area networks has still remained challenging because of technical and economical obstacles. Mainly the need for dedicated fibers and the strong dependence of the secret key rate on both loss budget and background noise in the quantum channel hinder a practical, flexible and robust implementation of QKD in current and next-generation optical metro networks. In this paper, we discuss these obstacles and present approaches to share existing fiber infrastructures among quantum and classical channels. Particularly, a proposal for a smooth integration of QKD in optical metro networks, which implies removing spurious background photons caused by lasers, amplifiers and nonlinear effects in optical fibers, is presented and discussed.
To date, QKD development has mostly focused in non-shared point-to-point links. Despite its limitations, this is the only technology commercially available today, and this makes it even more expensive and not easily deployable. The integration of QKD with the commercial network infrastructure would open the possibility of a scalable deployment and without requiring a massive initial investment QKD could reach a broader market. Current metro area networks are evolving towards optical, passive infrastructures and this opens up a good window of opportunity for QKD integration, since an all-optical clear path among two points in the network is no longer unfeasible or extremely expensive. However, the simultaneous propagation of quantum and classical signals over a shared link poses important problems due to the spilling of photons coming from classical signals. In this talk I’ll present current architectures for all optical metro networks and discuss our results in the integration of QKD in commercial networks
Quantum communications is an emerging field with many promising applications. Its usefulness and range of applicability in optical fiber will depend strongly on the extent to which quantum channels can be reliably transported over transparent reconfigurable optical networks, rather than being limited to dedicated point-to-point links. This presents a number of challenges, particularly when single-photon quantum and much higher power classical optical signals are combined onto a single physical infrastructure to take advantage of telecom networks built to carry conventional traffic. In this paper, we report on experimental demonstrations of successful quantum key distribution (QKD) in this complex environment, and on measurements of physical-layer impairments, including Raman scattering from classical optical channels, which can limit QKD performance. We then extend the analysis using analytical models incorporating impairments, to investigate QKD performance while multiplexed with conventional data channels at other wavelengths. Finally, we discuss the implications of these results for evaluating the most promising domains of use for QKD in real-world optical networks.
Quantum key distribution (QKD) is an emerging technology for secure distribution of keys between users linked by free-space or fiber optic transmission facilities. QKD has usually been designed for and operated over dedicated point-to-point links. However, the commercial world has been developing increasingly sophisticated fiber networks, with basic networking functions such as routing and multiplexing performed in the optical domain. One of the most important practical questions for the future of QKD is to what extent it can benefit from these trends, either to expand the capabilities of dedicated quantum networks, or to avoid the need for dedicated networks by combining quantum and conventional optical signals onto a single infrastructure. In this paper, we report on systematic investigations of these issues using a 1310-nm weak-coherent, phase-encoded B92 prototype QKD system developed by Los Alamos that includes the implementation of error correction, privacy amplification, and authentication. We have demonstrated reconfigurability of QKD networks via optical switching and successful QKD operation in the presence of amplified DWDM signals over 10 km of fiber. We have identified anti-Stokes Raman scattering of the DWDM signals in the fiber as a dominant transmission impairment for QKD, and developed filtering architectures to extend transmission distances to at least 25 km. We have also measured noise backgrounds and polarization variations in network fibers to understand applicability to real-world networks. We will discuss the implications of our results for the choice of QKD wavelengths, wavelength-spacing between QKD and conventional channels, and QKD network architectures.