Yes, Egypt left the internet. “This is a completely different situation from the modest Internet manipulation that took place in Tunisia, where specific routes were blocked, or Iran, where the Internet stayed up in a rate-limited form designed to make Internet connectivity painfully slow. The Egyptian government’s actions tonight have essentially wiped their country from the global map.” (via Renesys)
How exactly did they turn it off? “But how did the government actually do it? Is there a big kill switch inside Egyptian President Hosni Mubarak’s office? Do physical cables have to be destroyed? Can a lockdown like this work?” (via Gigaom). Update 1/31: Apparently, with a series of phone calls (via Wired) and not cutting the actual cables (via Ars Technica)
How activists are getting around this limitation… “[B]asically, there are three ways of getting information out right now — get access to the Noor ISP (which has about 8 percent of the market), use a land line to call someone, or use dial-up” (via Computerworld)
…and protecting themselves from retaliation? “Over the last three days, 120,000 people — most of them Egyptian — have downloaded Tor software, which helps activists protect their identity from surveillance by repressive regimes and get around blocked sites.” (via Boston Herald)
Update 1/31: Could it happen in the US? “My legislation would provide a mechanism for the government to work with the private sector in the event of a true cyber emergency,†Collins said in an e-mail Friday. “It would give our nation the best tools available to swiftly respond to a significant threat.†(also via Wired)