As protesters continue to clash with police in anti-government demonstrations, Egypt has pulled the plug on the Internet.
The cut-off happened just after midnight, local time, according to Internet monitoring firm Renesys, when the largest Internet Service Providers operating out of the country stopped providing the Border Gateway Protocol (BGP) routing information used to connect the rest of the world with computers in the Egypt.
Internet access isn't the only method of communications hit by the Egyptian government's blackout. It has ordered mobile phone operators to suspend service in some areas, according to Vodafone, which runs a network there. "Under Egyptian legislation, the authorities have the right to issue such an order and we are obliged to comply," the company said.
Egypt is experiencing its worst civil unrest in more than 30 years, as citizens have taken to the streets demanding an end to the government of President Hosni Mubarak.
Similar widespread outages have been blamed on cuts to undersea fiber-optic cables, but that doesn't seem to be what happened this time around, said Paul Ferguson, a researcher with security firm Trend Micro. An outage on a cable would not just effect Egypt, it would cut off all of sub-Saharan Africa." he said. "This is apparently a deliberate blackout."
"The Egyptian government appears to have ordered service providers to shut down all international connections to the Internet," Renesys said. "Critical European-Asian fiber-optic routes through Egypt appear to be unaffected for now. But 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."
Those four large providers -- Link Egypt, Vodafone/Raya, Telecom Egypt, and Etisalat Misr -- have dropped most of their Internet connectivity. Most Egyptian Web sites are now unreachable and people inside Egypt are largely unable to connect with the outside world using e-mail, instant messaging, or the Web.
But Egypt's Internet isolation is not complete. One service provider -- Noor Data Networks, a provider used by the Egyptian Stock Exchange -- is unaffected.
Twelve hours after the Internet shutdown began, the Egyptian Stock Exchange website was still accessible from outside the country.
On Twitter, a growing number of users, most of whom seem to be located outside of Egypt, are calling for users with a Wi-Fi router on Noor's ADSL or dial-up service to remove the password and share their Internet access with other users.
All told, about 88% of Egypt's networks have been cut off, according a blog entry on the Web site of network monitoring toolmaker, BGPmon.