THE CRTC received 75 complaints of traffic throttling last year against Internet providers large and small, some with multiple complaints.
"There are providers who have had multiple complaints, but it does go the whole gamut of types of service providers," the CRTC's Lynne Fancy said Thursday.
From an Internet user's perspective, traffic throttling can cause slower download speeds or jerky video streaming.
"It's generally individuals who are complaining," said Fancy, director general of competition, costing and regulatory implementation at the CRTC.
The Canadian Radio-television and Telecommunications Commission, which oversees the providers, didn't provide a list of companies that faced complaints in 2012.
Fancy said 11 of the 75 complaints were still being investigated.
Non-profit advocacy organization OpenMedia.ca said the onus remains on the consumer to report any traffic throttling to the CRTC.
Spokeswoman Lindsey Pinto said that process can be lengthy and complicated.
"The CRTC doesn't really have strong compliance or enforcement on this, so it's kind of up to the consumer to report to the CRTC when they see discriminatory practices taking place," Pinto said.
"We're going to continue to see problems until some kind of enforcement regime is put into place."
The CRTC doesn't have the power to fine an Internet service provider for traffic throttling, but Fancy said "nothing stops us from continuing to investigate..."
The CRTC doesn't have comparative statistics for 2011 because it changed the guidelines for complaints that year. But between Oct. 1 2009, and Sept. 30, 2011, there were 67 complaints, Fancy said.
Pinto said traffic throttling is largely done by the big telecom companies.
In one well-known example, the Canadian Gamers Organization complained Rogers Communications had been slowing traffic related to online games, which the company eventually admitted.
-- The Canadian Press