Continuous variable QKD in flexible optical networks for future quantum secure connectivity


Por: Moreolo, MS, Iqbal, M, Villegas, A, Casellas, R, Nadal, L, Muñoz, R

Publicada: 1 jun 2025
Resumen:
Future optical networks, envisioning the support of 6G services and related demanding requirements, should provide ultra-high-capacity and reliable connectivity, ensuring sustainability and security. Quantum key distribution (QKD) is a technology to address the limitations of classical cryptography, enabling quantum secure communications. Continuous variable QKD (CV-QKD) offers potential cost savings and enhanced compatibility with classical systems. This facilitates the integration within the network infrastructure, particularly in synergy with software-defined networking (SDN), further promoting interoperability and resource sharing/saving. For the adoption and practical implementation of CV-QKD, it is relevant to consider composable security and a finite number of symbols employed in the protocol (block size). In this work, we present the comparison of two models, to provide a figure of the required block size. We also assess the results using a simulation software. Furthermore, we explore a coexistence scenario considering a flexible grid, to exploit the CV-QKD capability of arbitrarily tuning the operating wavelength. This is a relevant feature enabling flexible allocation of the quantum channel to mitigate impairment and saving spectral resources. Considering realistic parameters aligned to commercially available CV-QKD systems and finite block size, we show an improvement with respect to our previous results. A minimum quantum-classical channel spacing of 112.5 GHz is required in a coexistence scenario with 8 x 200G transceivers and 9 dBm of total power over a 15 km link. In case of 10 dBm of total power, 125 GHz quantum-classical channel spacing is required to generate keys for practical implementation over the analyzed links. Finally, we discuss SDN aspects relevant for dynamic quantum channel allocation and flexible network management, enabling coexistence and efficient resource sharing, facilitating QKD technology integration in deployed networks. The presented results and envisioned potentialities of CV-QKD for practical implementation in optical networks pave the way for its adoption in the network infrastructure toward future quantum secure communications.

Filiaciones:
Moreolo, MS:
 Ctr Tecnol Telecomunicac Catalunya CTTC CERCA, Av CF Gauss 7, Barcelona 08860, Spain

Iqbal, M:
 Ctr Tecnol Telecomunicac Catalunya CTTC CERCA, Av CF Gauss 7, Barcelona 08860, Spain

Villegas, A:
 Ctr Tecnol Telecomunicac Catalunya CTTC CERCA, Av CF Gauss 7, Barcelona 08860, Spain

 LuxQuanta Technol SL, Esteve Terradas 1, Barcelona 08860, Spain

Casellas, R:
 Ctr Tecnol Telecomunicac Catalunya CTTC CERCA, Av CF Gauss 7, Barcelona 08860, Spain

Nadal, L:
 Ctr Tecnol Telecomunicac Catalunya CTTC CERCA, Av CF Gauss 7, Barcelona 08860, Spain

Muñoz, R:
 Ctr Tecnol Telecomunicac Catalunya CTTC CERCA, Av CF Gauss 7, Barcelona 08860, Spain
ISSN: 19430620





Journal of Optical Communications and Networking
Editorial
Institute of Electrical and Electronics Engineers Inc., 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA, Estados Unidos America
Tipo de documento: Article
Volumen: 17 Número: 6
Páginas: 71-82
WOS Id: 001494110700001
imagen Green Submitted, All Open Access; Green Open Access

FULL TEXT

imagen Accepted Version

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