Quantum Key Distribution (QKD) enables secure key exchange by leveraging quantum mechanics to provide theoretically unbreakable security. However, practical deploy ment of QKD networks is limited due to high costs, lack of interoperability of existing commercial products, and complex physical requirements. To address these challenges, digital twins of QKD networks provide an accessible and adaptable solution for testing and experimentation in emulated environments. This work presents the design of a digital twin model that emulates a QKD network under eavesdropping, allowing for realistic analysis of network behavior in the presence of security threats. As an initial stage, an emulation service of a QKD link with an eavesdropper has been implemented using the NetSquid simulator, offering a practical tool for testing QKD security. This model offers a versatile framework that can be adapted for use in different platforms and applications, providing not only a means to understand this threat and assess countermeasure effectiveness but also a method to analyze how attacks impact exchanged keys and the timing of key distribution.

About Ángela Diaz-Bricio

Angela Diaz-Bricio received her dual degree in Physics and Mathematics from the Universidad Complutense de Madrid in 2023. She completed her Master’s degree in Quantum Technologies and Engineering at Universidad Carlos III de Madrid in February 2025. In March 2025, she began her PhD at IMDEA Networks and Universidad Carlos III de Madrid, where she is actively involved in the MADQuantum-CM and QSNP projects while pursuing her doctoral studies.

This event will be conducted in English