Widespread telephone and broadcast outages caused by Hurricane Katrina show that the U.S. needs more reliable and redundant communications systems, including a better emergency warning system, the chairman of the U.S. Federal Communications Commission (FCC) said Thursday.

FCC Chairman Kevin Martin called for the U.S. government to incorporate the Internet into an emergency warning system that traditionally has been carried over television and radio stations, and he said telecommunications providers need to "take full advantage" of IP-based technologies to enhance their networks.

An emergency warning system "should incorporate the Internet, which was designed by the military for its robust network redundancy functionalities, and other advantages in technology so that officials can reach large numbers of people simultaneously through different communications media," Martin told the U.S. Senate Commerce, Science and Transportation Committee.

Emergency responders need more radio spectrum to communicate with each other, Martin added, and they need new technologies like so-called "smart" radios that can jump to different frequencies when some telecommunications providers aren't functioning, as happened when Hurricane Katrina hit the New Orleans area in late August.

BellSouth, the major provider of landline phone service in Louisiana, Mississippi and Alabama, lost connections on close to 2.5 million telephone lines following Katrina, said Bill Smith, the company's CTO. As of Tuesday morning, about 200,000 lines continued to be disconnected, he said.

About 20 million telephone calls did not go through the day after Katrina struck, Martin said. The hurricane knocked out 38 emergency 911 response centers, and three remained down as of Wednesday, he said. About 1,600 wireless telephone transmission sites were taken out by the hurricane, and 600 remain down, although all wireless switching centers in the area are now operational, he said.

Four television stations in the Gulf Coast region remain off the air, while three have returned to the air, Martin said. Thirty-six radio stations remain off the air, while several others have returned to the air.

Senators questioned why emergency 911 response centers didn't reroute calls to other centers as the hurricane approached. The technology exists, Martin said, but many emergency response centers did not have a plan for rerouting calls.

The IDG News Service is a Network World affiliate.