As uses such as IPTV and the sale of movies over the Web spread, providers fear Internet congestion is only going to get worse.

In its pre-hearing written submission to the commission, for example, Shaw insist that if it didn't use traffic management there would be a "catastrophic degradation" in service to its subscribers.

Opponents say the threat is overblown, worrying that traffic management instead threatens public access to the Internet. Others say the issue is one of who will control innovation on the Web.

For example, in its written submission, the Canadian Film and Television Production Association, representing several hundred content creators, said it fears trafficthrottling will result in Web providers "becoming the new gatekeepers of the Internet, with preferential access being granted to those favoured by ISPs."

It's already happening, Pelmorex Media, which runs The Weather Network cable TV, Internet and wireless sites, alleged in a written submission. "There are a number of commercial or business practices that are being employed by wireless network operators that limit access to their networks," the submission said in part. "Carriers routinely attempt to exercise control over the content or influence the meaning of the content they carry for the public." No wireless operators were named.