Virtually all Internet service in Egypt was shut down Thursday, in an apparent effort by the government to thwart the organization of anti-government protests.
That effort proved unsuccessful, as tens of thousands of protesters filled the streets Friday in Cairo, Alexandria, Mansoura, Suez, Minya, Assiut, and al-Arish.
A blog posting by the Internet-monitoring firm Renesys reported "the virtually simultaneous withdrawal of all routes to Egyptian networks in the Internet's global routing table" on January 27.
"In an action unprecedented in Internet history, the Egyptian government appears to have ordered service providers to shut down all international connections to the Internet," wrote James Cowie, Chief Technology Officer for Renesys.
"Every Egyptian provider, every business, bank, Internet cafe, website, school, embassy, and government office that relied on the big four Egyptian ISPs for their Internet connectivity is now cut off from the rest of the world."
Link Egypt, Vodafone/Raya, Telecom Egypt, Etisalat Misr, and all their customers and partners were, Renesys said, "off the air."
Cell-phone text and Blackberry Messenger services were all cut or operating sporadically in what appeared to be a move by authorities to disrupt the organization of demonstrations.
On Friday morning the Internet appeared to remain cut off in Cairo but was restored in some smaller cities.
Egyptians outside the country were posting updates on Twitter after getting information in voice calls from people inside the country.
Many urged their friends to keep up the flow of information over the phones.
CNET.com's Declan McCullagh and Elinor Mills report that a major service provider for Egypt, Italy-based Seabone, reported that there was no Internet traffic going into or out of the country after around 2:30 p.m. PT (12:30 a.m. local time), according to an Associated Press dispatch.
Al Jazeera English reported that the Mubarak government "denied disrupting communications networks" in advance of widespread protests planned at more than 30 mosques and churches on Friday, which is a day off in Egypt with banks and many businesses closed. (A spokesman for the Egyptian embassy in Washington, D.C. also denied earlier reports that Facebook and Twitter were selectively blocked.)
While the cause of the disruption remains unknown, it seems clear that yanking Egypt's Internet addresses was a conscious decision, not the result of a fiber cut or a natural disaster.
That means Egypt will be conducting a high-profile experiment in what happens when a country with a $500 billion GDP, one that's home to the pyramids and the Suez Canal, decides that Internet access should be restricted to a trickle.
That trickle can be found at the Noor Group, which appears to be the only Internet provider in Egypt that's fully functioning. (Cairo-based bloggers are speculating that its unique status grows out of its client list, which includes western firms, including ExxonMobil, Toyota, Hyatt, Nestle, Fedex, Coca-Cola, and Pfizer, plus the Egyptian stock exchange.)
An analysis posted by network analyst Andree Toonk, who runs a Web site devoted to monitoring networks, shows that yesterday there were 2,903 Egyptian networks publicly accessible via the Internet. Today, there are only 327 networks.
Noor is "the only provider that doesn't seem to be impacted by this," Toonk wrote.
That's led Egyptian Internet users, at least the ones still connected, to go on Twitter to urge others to use Noor's dial-up numbers if their own network was down.