Just after midnight on January 28, 2011, the government of Egypt, rocked by three straight days of massive antiregime protests organized in part through Facebook and other online social networks, did something unprecedented in the history of 21st-century telecommunications: it turned off the Internet. Exactly how it did this remains unclear, but the evidence suggests that five well-placed phone calls—one to each of the country’s biggest Internet service providers (ISPs)—may have been all it took. At 12:12 a.m. Cairo time, network routing records show, the leading ISP, Telecom Egypt, began shutting down its customers’ connections to the rest of the Internet, and in the course of the next 13 minutes, four other providers followed suit. By 12:40 a.m. the operation was complete. An estimated 93 percent of the Egyptian Internet was now unreachable. When the sun rose the next morning, the protesters made their way to Tahrir Square in almost total digital darkness.