On April 28, 2025, the Iberian Peninsula experienced its most severe electrical grid failure on record, causing widespread disruption across Spain, Portugal, and Andorra. While mobile networks collapsed, the Universidad Carlos III de Madrid maintained Wi-Fi connectivity through backup generators, providing a unique opportunity to study human behavior during a large-scale infrastructure failure. We analyze RADIUS authentication logs from the campus eduroam network, covering 2,819 users and 310 access points throughout the blackout event. Our analysis reveals three key findings. First, Wi-Fi occupancy spiked immediately after the outage as users migrated from failed mobile networks, followed by a gradual decline during the campus evacuation. Second, users redistributed spatially, shifting from interior spaces toward exterior areas, while cafeterias served as gathering points during the initial hours of the emergency. Third, the blackout led to increased network usage per user, transmitting more data per hour than under normal conditions. These findings demonstrate the value of Wi Fi sensing data for understanding collective behavior during emergencies and provide insights for designing resilient campus communication infrastructure.

About Romina Rodríguez

Romina Rodríguez is a PhD student at IMDEA Networks Institute under the supervision of Prof. Pablo Serrano. Her research focuses on machine learning and the analysis of WiFi network data to study human mobility and occupancy estimation in smart campus environments, with applications in energy efficiency, HVAC optimization, and emergency response.

Este evento se impartirá en inglés