On April 28, 2025, the Iberian Peninsula experienced a significant power outage that severely impacted services in Spain and Portugal. Philip Tellis from Akamai’s mPulse Developer Blog analyzed the traffic patterns during this event, revealing detailed insights into how users adapted to the outage. Tellis started by examining overall traffic patterns from Spain and Portugal over the preceding weeks, noting that Spain typically sees about 4.5 times more traffic than Portugal, reflecting their respective population sizes. The data showed a sharp drop in traffic between 12 PM and 1 PM Central European Summer Time (CEST) in Spain, which corresponds to 11 AM in Western European Summer Time (WEST) in Portugal. Traffic normalized around 2 AM on April 29. Drilling into the details, Tellis observed the traffic by device type at 5-minute intervals. In all four countries examined—Spain, Portugal, France, and Germany—desktop traffic declined significantly during typical lunch hours, with users shifting to mobile devices. During the outage, desktop traffic in Spain and Portugal dropped by 80%, while mobile traffic only decreased by 40%. Notably, mobile traffic remained higher than desktop traffic until the next morning, aligning with usual evening patterns when people move to mobile devices after work. Connection source analysis revealed that wired connections (including home, office, and public WiFi) saw a significant decline, dropping by about 50 percentage points in Spain and Portugal. Simultaneously, cellular network usage in Portugal increased by 30 percentage points, indicating that many users relied on mobile networks to stay connected. Regarding user destinations, Tellis categorized websites by industry to understand which services were most accessed during the outage. In Portugal, which faced the blackout starting at 11:33 AM local time, there was a notable surge in traffic to news websites as people sought information about the situation. Government websites also saw increased traffic, particularly those providing updates and advisories. Additionally, there was a sudden interest in food safety and food handling sites, likely because users were concerned about the safety of their perishables without refrigeration. These sites had no prior traffic in the weeks leading up to the event, highlighting the unique circumstances created by the outage. In Spain, where the power outage began slightly later at 12:33 PM local time, users primarily turned to government websites for information rather than news sites. There was also a steady stream of visits to travel-related websites, suggesting people were checking the impact on their travel plans. Both countries saw a decrease in retail, entertainment, and financial activities, emphasizing the disruption caused by the loss of power. To understand the sustainability of mobile connectivity, Tellis analyzed phone battery levels during the outage. Comparing the data to the previous week and with other EU countries, he found that during the peak of the outage, phone battery levels in Spain and Portugal were about 10 percentage points lower than usual. This indicates that users were actively using their mobile devices despite the power outage. As partial power began to restore, first in Portugal and then in Spain, battery levels returned to normal. There was a minor second drop in battery levels later at night, coinciding with more users coming back online, but things stabilized quickly thereafter. Industry insiders note that the ability of certain websites to remain accessible during such a massive power outage underscores the resilience of modern internet infrastructure, particularly through the use of edge nodes and backup power systems. Akamai, known for its content delivery network, emphasizes that its distributed architecture and emergency preparedness measures allowed critical information services to stay online, ensuring that users could access essential resources. Akamai is a global content delivery network (CDN) and cloud service provider, renowned for its robust infrastructure and reliability in delivering web content. The company’s mPulse tool, used for this analysis, provides deep insights into web and mobile traffic patterns, helping businesses optimize their digital performance and user experience. This event highlights the critical role of mobile networks and cloud providers in maintaining internet connectivity during emergencies, reinforcing the need for infrastructure resilience and user access to reliable information sources.