Hot on the heels of the news that Bell Canada is cutting some of its Internet throttling with wholesale customers comes some really -- and I mean really -- interesting data on throttling worldwide. Ladies and gentlemen, presenting the world's absolute worst throttler (since 2008): Rogers.

According to researchers who used M-Labs, a project launched by Google in 2009 that allows Internet users to keep tabs on how their service providers are slowing connections, Canada's biggest cable Internet provider has been the worst at slowing down applications, primarily peer-to-peer services such as BitTorrent, using deep-packet inspection technology.

M-Labs gives users tools to test their connections and, according to its methodology:

The column on the far right shows the percentage of times Glasnost tests indicated that the ISP was manipulating BitTorrent using DPI. The number of valid tests is important because the more valid tests done, the more reliable the results in the last column. E.g., ISPs for whom we have only 11-30 tests per quarter (only one to two tests per week) will be highly variable and thus less reliable than ISPs for whom we have >450 tests per quarter.

The only ISP that showed up in the 90%-plus category with more than 450 tests: Rogers. Also bad was UPC Ireland, but it fell short in total comparisons to its Canadian cousin.

How did other ISPs compare? Well, Comcast -- the company that elicited sanctions from the FCC for its throttling -- only ever slowed about 49% of its connections, back in the second quarter of 2008. Bell, the Canadian ISP that has taken the most flak for slowing down connections, ironically didn't fare all that badly compared to its main rival.

Here are the most recent results for Canadian ISPs and the percentage of connections they throttled in the first quarter of 2010:

Shaw: 14%
Bell: 16%
Rogers: 78%
Telus: 6%
Videotron: 3%
Bell Aliant: 6%
Cogeco: 46%
Sasktel: 5%
MTS: 6%

The first three ISPs on that list had more than 450 samples, while Telus had between 151 and 450. The rest had between 31 and 150.

Here are the worst worldwide in the most recent quarter, with the sample size following:

UPC Poland: 87%, 91-150
KT Corp (South Korea): 84%, 31-60
GTS Novera (Czech): 80%, 11-30
Rogers: 78%, 450+

As the methodology states, the larger the sample size, the more accurate the result, so Rogers looks particularly poor on that list.

Given this information, is it any wonder gamers are fuming at Rogers for its throttling, which isn't just affecting peer-to-peer traffic but also perfectly legal applications such as World of Warcraft? Isn't it about time the CRTC -- which laughably touts the world's best net neutrality rules -- got off its keester and did something?

UPDATE: Milton Mueller, the principal investigator behind the findings, wrote a paper looking at some of the results in more detail. Check out "Deep Packet Inspection and Bandwidth Management," which compares throttling in the United States and Canada. Some interesting takeaways include the facts that Rogers and Cogeco both started throttling on the same day, July 1, 2008 (how's that for coincidence?) and throttling by U.S. ISPs is about 11% overall, compared to 33% in Canada.

UPDATE: Some people were wondering how ISPs who say they don't throttle, such as Telus and Videotron, showed up in the tests. According to the explanatory notes of the study, the tests seemed to generate false positives of around 10% prior to August 2009 and 4-5% after that, which pretty much matches or erases the results for the ISPs in question. If anything, the results prove those companies aren't throttling. With that said, the error margin still doesn't do much to improve the positions of the top throttlers.

This post was previously published on www.wordsbynowak.com

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