Taiwan sharply reduced internet speeds during air-raid drills, simulating a coordinated attack on communications for the first time. Sirens emptied streets and sent residents into shelters while video calls, streaming, mobile payments and data-heavy social platforms became slow or unusable.
The network exercise ran on two separate days across 14 cities and counties in northern and central Taiwan, areas containing roughly 70 percent of the island's 23 million people. The disruption was designed to make the emergency tangible: workplace messages failed to arrive, videos barely loaded and some social-media messages took about 30 seconds to send.
Civil-defense participants also tested a way to communicate without the internet. Wang Chen-wen, who leads a local training group, used a small device linked to her phone by Bluetooth to send text through long-range, low-power radio signals. Messages posted through an open-source platform reached users in other Taipei districts, although not every attempt succeeded.
Authorities want residents to prepare alternative channels before a crisis and regard the inconvenience as part of the lesson. Tzeng Yi-suo of the Institute for National Defense and Security Research said repeated exercises can build public awareness while revealing which backup systems work when ordinary communications are restricted.
The test reflects concern over the 16 international and 10 domestic undersea cables that form Taiwan's digital lifeline. Several have been damaged in incidents involving Chinese or China-linked vessels. Taiwan's coast guard has described such pressure as a grey-zone tactic that consumes resources without crossing the threshold of open war; two Chinese captains were convicted in 2025 in separate cable cases.
Taiwan is therefore pursuing layered alternatives so one failure cannot isolate the island. Low-Earth-orbit satellite services are among the options, drawing on Ukraine's experience after conventional infrastructure was damaged. Legislative amendments approved in July could allow Starlink into the market, though Elon Musk's extensive business interests in China have raised concerns about dependence on that network.
Officials and civil-defense organizers see reliable information as essential when an outage creates uncertainty and fear that hostile actors could exploit. The exercise turned that strategic problem into an everyday experience, testing both national infrastructure and household habits while encouraging residents to develop a basic communications plan before an emergency occurs.
