The man often called the father of the Internet has said that the future of the Internet is at risk. Vint Cerf, co-designer of TCP/IP, asked US Congress to pass a law prohibiting broadband providers from discriminating against competing web applications and computer devices.

Congress needs to keep large broadband carriers from favouring their own services and slowing down access to competitors and from charging some websites for faster speeds, said Cerf, vice president and chief Internet evangelist at Google.

But representatives of the large telecom carriers and the cable television industry promised that they would not block or slow access to websites and applications.

"Our commitment to our customers, our commitment to you is this: We will not block, impair or degrade content, applications or service," said Walter McCormick, president and chief executive of the United States Telecom Association (USTA), representing large telecom carriers. "That is the plainest, most direct way I know to address the concerns that have been raised."

Echoing consumer group concerns that the newly-deregulated telecom carriers will try to give their own services better speeds over broadband networks, Cerf asked the Senate Commerce, Science and Transportation Committee to adopt a 'Net neutrality law, requiring broadband providers to allow customers to go to any legal websites, attach any legal devices and run any legal applications on their networks. If large broadband providers are allowed to charge websites or web-based application vendors extra for customer access, small innovative companies will get frozen out, he said.

"Nothing less than the future of the Internet is at stake in these discussions," said Cerf. "We must preserve neutrality in the system in order to allow the new Googles of the world, the new Yahoos, the new Amazons to form. We risk losing the Internet as catalyst for consumer choice, for economic growth, for technological innovation and for global competitiveness."

While USTA and the National Cable and Telecommunications Association promised not to block or impair websites and services, some consumer groups have criticized proposals by AT&T and BellSouth to ringfence a high-speed broadband service for their own video services. Many consumer groups have also pointed to recent comments from AT&T and Verizon Communications executives indicating they want to charge sites like Google for delivering customers to them.

On Tuesday, The Washington Post quoted Verizon Vice President and Deputy General Counsel John Thorne as complaining that websites like Google are getting a "free lunch" by using telecom carriers' networks. "The network builders are spending a fortune constructing and maintaining the networks that Google intends to ride on with nothing but cheap servers," Thorne was quoted as saying. "It is enjoying a free lunch that should, by any rational account, be the lunch of the facilities providers."

Thorne's comments were similar to ones made by AT&T Chief Executive Officer Ed Whitacre in November, when he complained to Business Week about companies like Google and Vonage Holdings, a VoIP provider. "Now what they would like to do is use my pipes free, but I ain't going to let them do that because we have spent this capital and we have to have a return on it," Whitacre said then.

Some senators questioned those comments from AT&T and Verizon. "This is not a free lunch," said Senator Byron Dorgan, a North Dakota Democrat. "I paid for the capability to have DSL or cable broadband."

But broadband providers said they could be restricted from offering new services and partnering with other companies if an Internet neutrality law passes. And some Republican senators said Internet freedoms need to be balanced with the ability of the broadband providers to make money.

"Everybody agrees that we want to the Internet to be free," said Senator John Ensign, a Nevada Republican. "We also have to recognise there's a balance. You do deserve a return on your investment."