On January 20, 2026, the Universidad Politécnica de Madrid (UPM) and Q*Bird announced the deployment of Spain’s first multi-node measurement-device-independent quantum key distribution (MDI-QKD) network. The network connected three end nodes across high-security operational environments, with installations at two sites of the Instituto Nacional de Técnica Aeroespacial (INTA) and one at the Ministry of the Interior’s SGSICS, all in Madrid.
The network used a hub-and-spoke topology with Q*Bird’s Falqon® Series, featuring fiber distances of 30 to 50 kilometers from the center hub to each user end node. The MDI-QKD architecture ensured that all detectors were located at the center hub, which never handled encryption keys, eliminating vulnerabilities associated with detector-side attacks on traditional QKD systems.
The deployment was part of the Madrid Quantum Communication Infrastructure (MadQCI) initiative and contributed to the EuroQCI initiative. UPM researchers said the network provided a platform for evaluating key performance metrics and optimizing configurations for high-security scalable deployments, demonstrating that industrial-grade MDI-QKD was technically feasible for modern critical infrastructure and government applications.