UPDATE: Is Comcast Choking Off BitTorrent?

Comcast is using software to slow down and interrupt some of its customers’ BitTorrent file transfers, TorrentFreak reports. The story doesn’t identify how many Comcast subs are involved or where those subs live. Comcast hasn’t replied to our queries; we’ll update if they do. Update: a Comcast rep says the company isn’t manipulating anyone’s file transfers.

If Comcast is indeed preventing it subs from using its broadband service because of the software they’re using, the largest U.S. cable company will have given “net neutrality” supporters a boatload of ammo. Then again, they should be careful about how they deploy it — this could be a very tricky argument for them to make.

That’s because many, if not most, BitTorrent users employ the software to swap pirated music, movies, games and the like. And Comcast’s Terms Of Use are explicit about the company’s right to kick out any user who violates copyright law.

So if net neutrality supporters have a case here, it’s a limited one: It would be fine for Comcast to shut off the service of BitTorrent users who are sharing copies of The Simpsons Movie — if they know that’s what they’re doing. But if Comcast is simply slowing down or shutting off BitTorrent transfers across the board, they have a problem. There are plenty of legitimate uses for BitTorrent, like Linux installer kits, video podcasts, and vacation videos.