Internet remains reliable nationwide.

• Position: Homeland Security - Brief article

What would happen to Internet reliability in the U.S. if terrorists were able to knock out various physical components of the network? The good news is that it would be very difficult to cause major disruptions across the country, although destruction of some key parts seriously could degrade Internet quality.

When it comes to the Internet, there is strength in numbers. There are so many interconnections within the network that it would be difficult to find enough targets, and the right targets, to do serious damage to Internet reliability nationwide," notes Morton O'Kelly, professor of geography at Ohio State University, Columbus.

The researchers simulated disruption or failures of parts of the network to see what would happen to Internet connectivity between various pairs of cities--946 pairs in all. However, they assumed that not all the backbone providers in a network node would be disabled at once, and that peering agreements would allow at least some Internet traffic to continue flowing.

For some city pairs, disruptions in nearly a dozen...