Bell has until Sept. 11 to respond to the CRTC's questions about internet usage billing.

The CRTC wants Bell Canada to explain the prices it plans to charge wholesale internet customers when it rolls out a new billing model based on monthly usage later this year.

In a letter dated Aug. 20, the Canadian Radio-television and Telecommunications Commission said it wants Bell to explain how it has calculated the prices wholesale customers such as MTS Allstream and Teksavvy will be charged, and how the new usage-based billing model will reduce internet traffic during peak times.

The CRTC two weeks ago provisionally granted Bell's request to impose usage-based billing on wholesale customers, which are companies that rent parts of its network through a process known as Gateway Access Service (GAS) to provide their own retail internet products.

The decision angered Bell's wholesale customers, who said that offering generous monthly usage to customers — sometimes in the hundreds of gigabytes versus the 50 or 60 Bell typically offers — was the only way they could differentiate their services. Usage-based billing would make such large usage plans prohibitively expensive to offer, they said.

The ruling also prompted anger among consumers, who accused the regulator of kow-towing to Bell. An online petition to dissolve the CRTC and replace it with a new regulator has amassed more than 5,100 signatures since the decision.

Bell said that instituting usage-based billing, both on its own retail customers and its wholesalers, is part of its strategy to combat rapidly growing internet traffic. Throttling, or the slowing down of certain uses of the internet such as peer-to-peer file sharing, is another key part of that strategy. The CRTC has now approved both Bell's extension of throttling and usage-based billing to its wholesale customers.

The regulator said it wants the pricing justifications from Bell because of concerns voiced by MTS Allstream.

"MTS Allstream submitted that GAS is the only means that competitive internet service providers have of providing high-speed internet accesses to all of the end customers that Bell Canada serves and that it is essential that the competitor ISPs be able to challenge Bell Canada's cost studies," wrote Paul Godin, director general of competition, costing and tariffs for the CRTC.

"MTS thus argued that the commission should require Bell Canada to provide sufficient information on the public record to allow interested parties to make meaningful comments."

Bell has until Sept. 11 to answer the CRTC's questions, at which point other parties — such as wholesale customers and consumer groups — will be able to request the public disclosure of that information.

Among the explanations requested by the CRTC are:

• The reasons for different monthly usage limits, such as 2 gigabytes, 20 gigabytes and 60 gigabytes.
• The discrepancies between Bell's usage data and those of wholesalers, which in some cases differed by 800 per cent.
• Why wholesale customers will be subjected to being "restricted, suspended or disconnected" for over-usage if they will already be paying for excess usage.
• How Bell accounts for customers using its Voice over Internet Protocol services.
• Maintenance details of its network.

A spokesman for Bell did not return a request for comment. Usage-based billing of wholesale customers is scheduled to take effect in mid-November.