Comcast is reportedly stabbing at the heart of the file transfer protocol BitTorrent by preventing users from seeding torrent files. Seeds are completed BitTorrent downloads shared with other users; without seeders, the BitTorrent protocol does not work, much the way a garden can’t grow without seeds. Comcast’s draconian throttling solution utilizes a program from Sandvine that affects all files distributed through BitTorrent, regardless of whether the shared file is an illegally downloaded movie, or a legal distribution of Linux. From TorrentFreak: The throttling works like this…
A few seconds after you connect to someone in the swarm the Sandvine application sends a peer reset message (RST flag) and the upload immediately stops. Most vulnerable are users in a relatively small swarm where you only have a couple of peers you can upload the file to. Only seeding seems to be prevented, most users are able to upload to others while the download is still going, but once the download is finished, the upload speed drops to 0. Some users also report a significant drop in their download speeds, but this seems to be less widespread. Worse on private trackers, likely that this is because of the smaller swarm size.
According to Light Reading, Comcast has issued a carefully worded denial:
“We’re not blocking access to any application, and we don’t throttle any traffic,” says Charlie Douglas, a Comcast spokesman.
Douglas didn’t explicitly deny the use of deep packet inspection or traffic shaping products. “[Comcast] has a responsibility to manage our network to ensure our customers have the best service, and we use available technologies to do so.”
We’d be happy to live in a world where the absence of this unabashed corporate machismo made government regulation unnecessary, but Comcast would rather cry free market and gallivant over their users in search of more profit. Their own actions are the most convincing argument in favor of net neutrality.
Comcast Throttles BitTorrent Traffic, Seeding Impossible [TorrentFreak]