Thousands of viewers have embraced CBC-TV's experiment with BitTorrent, but many Canadians have found their attempts to access a CBC show online restricted by their internet service providers.

On Sunday, CBC offered a final episode of reality TV program Canada's Next Great Prime Minister for download via BitTorrent, a file-sharing service.

The release was an experiment for the public broadcaster in new ways of offering its programming.

Downloads were in the thousands, said Tessa Sproule, executive in charge of digital programming for factual entertainment at CBC Television.

It is impossible to tell how many people actually saw the program because the files are passed from one computer user to another through BitTorrent, she added.

"It was very promising," Sproule told CBC News. "People around the world are seeing the file, probably because it's the first time.… We're very happy about it."

ISP bottlenecks

However, downloaders who blogged about the experience on the Canada's Next Great Prime Minister site complained about very long periods required to download the show.

One user received a notice that it could take 2½ hours to download, while another was quoted 11 hours.

The bottleneck is occurring because ISPs such as Rogers and Bell limit the amount of bandwidth allocated for file-swapping on BitTorrent.

The controversial practice, called traffic shaping, is meant to stop illegal downloading through BitTorrent. But it also slows the times on legal downloads such as Canada's Next Great Prime Minister.

Michael Geist, an Ottawa-based advocate of open sharing over the internet, called the CBC experiment an "enlightened approach to content distribution."

But he warned that ISP practices could get in the way.

"It would be ironic if ISP network management practices ensured that viewers outside the country enjoyed better access to the program than the Canadian taxpayers who helped fund its creation," he wrote in his blog.

Some people posting on the show blog said they'd left their computers running to help speed up downloading through BitTorrent for others.

Most users posting on the blog welcomed the CBC's experiment with BitTorrent.

"With the state of affairs of Canada's fading telecommunications industry, it's fantastic to see that CBC is pressing new boundaries. Kudos on finding new ways to provide Canadian content," said a user called Bob.

Others asked for more content to be delivered this way, including favourite shows such as Jpod, Rick Mercer Report, Fifth Estate and the news.

"I'd like to see more content delivered in this way, without restriction and I can tell you that the majority do not mind ad placement within the content," said a user called Steven G.

There were complaints about the quality of the download, with some saying the images were distorted.

Sproule said CBC is working on refining the quality of broadcast via BitTorrent.