In a move likely to be cheered by heavy Internet users and small Internet companies alike, Bell Canada has told its business partners that it’s moving away from throttling traffic on its Internet networks.

But critics are already turning their attention to other Canadian Internet service providers that have admitted to slowing down Internet traffic, particularly on peer-to-peer file-sharing networks or on online video games. They argue that Bell's move away from traffic throttling shows the practice is unnecessary, and therefore a violation of federal rules governing the Internet.

Bell sent a letter earlier this week to Internet service providers that use the company's DSL network, informing them that starting next month the company would begin to transfer its customers to network facilities that don't use traffic-shaping software.

In the letter, obtained by Internet law expert Michael Geist and OpenMedia.ca, Bell said it had started slowing Internet traffic in March, 2008, "to address congestion on the network due to increased use of peer-to-peer file-sharing during peak periods. While congestion still exists, the impact of peer-to-peer file-sharing applications on congestion has reduced."

It is that admission -- that file-sharing is no longer causing critical congestion issues -- that has critics calling for an end to traffic throttling altogether.

Bell's move “draws further into question why Rogers and other big Internet service providers continue to employ the anti-competitive tactic,” OpenMedia said in a statement Wednesday.

University of Ottawa professor Michael Geist raised the prospect that Bell's continued use of traffic throttling, however temporary, may now violate the CRTC's rules, which require that traffic shaping "results in discrimination or preference as little as reasonably possible."

Geist suggested the CRTC look into other Internet providers "who deploy broad based throttling practices (Rogers, Cogeco), which may not be reasonable under the CRTC policy."

Traffic throttling has been a contentious issue in Canada for the past three years, ever since Bell, Rogers and other large owners of Internet infrastructure began the practice as a response to growing congestion on their networks.

The move upset not only many Internet users, but small Internet providers as well, who rely on the phone line networks of Bell Canada, or the cable networks of Rogers, Videotron, Cogeco and others, to deliver Internet service.

The internet resellers argued traffic throttling amounted to "censorship" and forced them to provide a sub-standard service to their customers.

A similar problem arose with usage-based billing -- the practice, recently introduced in Canada, of charging overage fees to customers who exceed a certain amount of data per month on their Internet connection. Large ISPs argued it's only fair to charge customers more if they use more bandwidth.

But because companies like Bell and Rogers planned to charge the overage fees to their resellers, smaller ISPs argued UBB would hobble their business and make it impossible to offer competitive services.

The practice is also opposed by Netflix, whose online movie service consumes large amounts of bandwidth. The company has said that UBB threatens its continued suvival in Canada. Notably, many of the owners of Internet infrastructure also own on-demand movie services that compete with Netflix.

After ruling in favour of UBB last fall, then augmenting its policy earlier this year, the CRTC was forced to reconsider its position. It is expected to issue a final ruling on usage-based billing this fall.