NEW YORK - Comcast Corp. actively interferes with attempts by some of its high-speed Internet subscribers to share files online, a move that runs coun

Same song, second verse. This article contains some additional information about a test done by the AP.


Comcast has been "caught" blocking BitTorrent traffic in some areas, according to tests performed by the Associated Press. The news organization claims to have confirmed that Comcast is blocking—or at least seriously slowing down—BitTorrent transfers, regardless of whether the content is legal or not. If true, Comcast's actions have serious implications for sharing information online, and by proxy, Net Neutrality.

The AP was tipped off to the possible P2P blockage by a reader who had noticed serious slowdowns on his Comcast connection. The organization then proceeded to perform a number of tests—three, to be exact—on two computers in cities on both the east and west coasts. AP chose to download a copy of the King James Bible through BitTorrent (because it is an uncopyrighted work) and went to work. In two out of its three tests, the downloads were blocked altogether, while in the remaining test, the download started after a 10-minute delay.

AP believes that the reason for the block and delay was due to reset packets being sent back from what claimed to be other torrent users—including the AP's second computer. "However, the traffic analyzer software running on each computer showed that neither computer actually sent the packets," wrote the AP, indicating that the packets were sent by a mysterious middle party. Further, the AP says that when it performed traffic analysis on another computer torrenting files over Time Warner Cable, over half of the reset packets came from the addresses of Comcast subscribers. This is curious, since Comcast's 12.4 million subscribers only make up about 20 percent of US broadband subscribers.

Comcast spokesperson Charlie Douglas told the AP that the company doesn't block access to BitTorrent, but did not elaborate on his definition of "access" (.torrent files can be downloaded just fine, for example). However, Douglas also said that Comcast does use something to keep the network running smoothly. "We have a responsibility to manage our network to ensure all our customers have the best broadband experience possible," he said. "This means we use the latest technologies to manage our network to provide a quality experience for all Comcast subscribers."

We're not entirely sure that the AP's tests are as conclusive as it seems to believe—after all, two tests in three cities does not constitute an exhaustive data set. We do, however, think that the AP—and others who have noticed the issue—are onto something. Everyone has been trying to figure out what, exactly, Comcast is doing to throttle P2P traffic in certain markets, and Comcast sending reset packets on behalf of Comcast subscribers is a probable cause. But doing so is also misleading, and could even be construed as an attack on other torrent users who are not using Comcast. There are other, more direct methods to go about filtering BitTorrent content, such as deep packet inspection. However, it has been argued that overprovisioning a neutral network is still cheaper than investing money on technology to fight such traffic.

Comcast's actions also have implications for net neutrality. But that's no secret, as Comcast has been among the plethora of ISPs that regularly oppose net neutrality legislation. The ISPs like to argue that, by allowing all Internet traffic to pass through the pipes equally, they could lose money because of overall network slowdowns. But customers pay for broadband service for a variety of reasons, not the least of which is so that they can get full, high-speed access to the content of their choice.

As always, comments are welcome.