Authors: Juan Carlos Hernández-Hernández, David Larrabeiti, María Calderón, Ignacio Soto, Bruno Cimoli, Hui Liu, Idelfonso Tafur Monroy
Journal: Future Generation Computer Systems, Vol. 164, 2025, Article 107557, ISSN 0167-739X. DOI: 10.1016/j.future.2024.107557
🔍 Summary
In this paper we propose and evaluate an approach for designing wide-area trusted-relay Quantum Key Distribution Networks (QKDNs) in which QKD transceivers are time-shared via optical switches under SDN control. We introduce the model named qTDM-QKDN, and formulate a Mixed Integer Linear Programming model (qTDM-MILP) plus a heuristic algorithm (qTDM-HA) for resource allocation (transceiver counts, optical switch ports, per-neighbor time fractions) given target secret-key–rate demands.
Key results show that by using TDM to share QKD transceivers you can reduce network cost (10-40 %) compared with networks where each pair has dedicated transceivers (non-TDM). The work also investigates how the working cycle duration TTT affects performance and resource requirements.
🚀 Why It Matters
- Enables more cost-efficient deployment of QKD networks by sharing expensive hardware resources.
- Provides practical optimisation tools (MILP + heuristic) for network designers and operators.
- Supports scaling of QKD infrastructure a key enabler for future quantum-secure communications.
- Offers insight into scheduling/time-multiplexing strategies that complement spatial and wavelength domain sharing.