Lawmakers in Congress are scheduled to vote today on a landmark bill that consumer advocates and some of the biggest names in the tech world say would change the Internet as we know it, creating fast lanes and slow lanes for Web access.

The issue of so-called net neutrality, as in network neutrality, is at the heart of legislation that represents the most sweeping overhaul of telecom law since the Telecommunications Act of 1996.

The question is whether network providers like AT&T and Verizon should have the ability to charge some Web sites fees for faster access speeds -- and whether such a two-tier system inherently discriminates against any site that doesn't pony up extra cash.

It also has broader ramifications as the phone companies prepare to flood existing bandwidth with their own video services, potentially creating bottlenecks for other online content.

"The Internet could be fundamentally altered by this," said Rep. Ed Markey, D-Mass., one of Congress' leading authorities on telecom issues and a ranking member of the House Energy and Commerce Committee's telecom subcommittee.

"The more people learn about this, the more they'll understand we're heading toward a system of informational apartheid," he told me.

Markey said Republican backers of the legislation -- titled the Communications Opportunity, Promotion and Enhancement Act of 2006 -- are expected to prevail in today's subcommittee vote.

A vote by the full House is possible by June, and the Senate is likely to take up the matter shortly thereafter. The bill's chief sponsor, Rep. Joe Barton, a Texas Republican who chairs the Energy and Commerce Committee, has said he expects President Bush to sign it into law by the end of the year.

There are other components to the bill. One would allow phone companies to bypass municipal approvals when rolling out video services (an exemption not offered cable providers). Another would allow cities to develop local wireless networks without first getting the OK from state officials.

But it's net neutrality that could end up having the most profound impact on the millions of people for whom the Internet has become a core part of their daily lives.

"The Internet has always been open and operated on a best-effort basis," said Gigi Sohn, president of Public Knowledge, a Washington digital-rights group. "That means no one's messing with all the bits. Everyone's bits get the same treatment.

"When the broadband provider inserts himself in the middle of this system, which is what this bill would allow, the provider becomes Internet God. He can determine which bits get priority and which ones don't."

It's not as though an entirely new (and faster) network will be built for well-heeled Web sites. Rather, the existing network will remain, but telecom providers will have the ability to determine which transmissions get where they're going more quickly and securely.

Seeking higher prices

The phone companies argue that they need to charge higher prices to companies that require more-reliable networks, or that are transferring unusually large files to customers, such as online movies.

"Our industry has stated that it will not block, impair or degrade consumer access to the Internet," Walter McCormick, head of the U.S. Telecom Association, testified before lawmakers last week.

Here's the problem: Let's say Amazon.com pays extra fees to have its site load faster on people's browsers. And let's say a smaller online bookstore can't afford the fees and thus its site loads more slowly.

Assuming book prices at both sites are comparable, which one will get more business over the long haul? Most likely, the one with better performance -- in this case, Amazon. The smaller upstart can't compete.

By the same token, would Google ever have caught on if it operated noticeably slower than other search engines? Would the next Google-to-be now being developed by some college student even have a shot if it can't afford toll charges for the Net's fast lane?

Warning about Internet

Last month, a consortium of some of the biggest names in the tech business submitted a letter to the Energy and Commerce Committee warning that "the Internet is at risk of losing the openness that has made it an engine for phenomenal social and economic growth."

"Consumers in the marketplace, and not network operators, should decide what content and services succeed or fail," the letter said, adding that this "must be guaranteed by a meaningful and enforceable net neutrality requirement."

Companies submitting the letter included Amazon, eBay, Google, Microsoft, TiVo, Yahoo and dozens of other top tech outfits.

The legislation now before lawmakers has been stripped of more- stringent requirements submitted by Democratic politicians. The bill would allow the Federal Communications Commission to decide disputes about Web access only on a case-by-case basis, not as a matter of broad policy.

It would also prohibit the FCC from writing any new net-neutrality rules in the future.

Markey said the final draft of the bill is the result of aggressive lobbying by phone companies.

"This bill is of, for and by the Bells," he said. "It basically gives AT&T and Verizon everything they want."

The phone companies have responded to such criticism by repeatedly insisting that they have no intention of blocking access to any Web sites or worsening anyone's performance.

"AT&T will not block access to the public Internet or degrade service, period," Ed Whitacre, the company's chairman, told an industry conference in Las Vegas last week.

But he and other telecom execs also maintain that they see nothing wrong with some content providers paying a premium for reliable service -- and, by inference, for everyone else to accept less-than-optimal network reliability.

"If someone wants to transmit a high-quality service with no interruptions and 'guaranteed this, guaranteed that,' they should be willing to pay for that," Whitacre told an interviewer in January.

Google called freeloader

A few days later, a top Verizon exec said content providers like Google are freeloading off the phone companies' networks.

"The network builders are spending a fortune constructing and maintaining the networks that Google intends to ride on with nothing but cheap servers," John Thorne, a Verizon senior vice president, told an industry conference.

"It is enjoying a free lunch that should, by any rational account, be the lunch of the facilities providers," he said.

Representatives of AT&T and Verizon were unavailable to comment further.

First off, the phone companies don't own the Internet. Without all that content on the Web, all they'd have is a bunch of wires awaiting phone calls (and no steady profits from monthly DSL charges).

Moreover, net neutrality has never been about blocking people from certain sites or services -- that's a red herring.

Net neutrality is about ensuring that all denizens of cyberspace have access to the same thoroughfares, and not relegating some content to country lanes while preferred data zips along the turnpike.

It's about ensuring that no sites or services are discriminated against -- by providers or consumers -- simply because they can't afford special treatment.

Sohn at Public Knowledge said the Internet's growing pains could be solved by the phone companies increasing broadband capacity, creating room for their new video services and everything else that traverses the electronic ether.

"But if they build bigger pipes, nobody would pay extra for faster access," she observed. "With bigger pipes, every site has faster access. The providers have no incentive to build out their networks."

And so we approach an era of two-tier Net access -- high-speed haves and have-nots.

"The Internet isn't the be-all, end-all of everything," Sohn said. "But it is the most democratic medium the world has ever known. Everyone has an equal voice.

"That's about to change."