As it wages an escalating civil war, Libya has once again cut Internet service in and out of the country.
Libya blocked Internet traffic, and then quickly restored it, two weeks ago. But this time it's doing things a little differently.
In February, Libya took a cue from Egypt and used the Border Gateway Protocol (BGP) to tell the world's routers to essentially steer clear of Libyan Internet space. Now, the country has erected a firewall around all of its Internet traffic. "They're blocking all the traffic," said Renesys General Manager Earl Zmijewski. "The routes are still up, but there's no traffic flowing. It's as if all the roads are open, but all the cars are blocked."
With international calls getting stronger for President Moammar Gadhafi to step down, this latest move appears to be an attempt to cut the flow of information to and from the north African country.
Withdrawing the BGP routes is akin to hitting an Internet kill switch, making it impossible for any Internet traffic to flow in or out of the country. With this latest firewall technique, Gadhafi's government could selectively allow some computer, the president's for example, to use the Internet.
Zmijewski does not know what, if any, systems have Internet access in Libya.
Besides Egypt, other nations such as Myanmar in 2007 and Nepal in 2005 have taken similar steps to kill Internet access, and China selectively cuts access to certain parts of the Internet using its so-called Great Firewall of China. But with 400 million users, compared to hundreds of thousands in Libya, China's firewall is an extremely complicated work of engineering.
Putting up a country-wide firewall is a relatively simple thing for Gadhafi's government, because the nation's Internet connections have a single choke point, the state-owned Libya Telecom & Technology (LTT). By simply changing router settings at LTT, the government could put up the firewall nation-wide, Zmijewski said.