It’s Comcastic: Is Comcast Blocking Users From Seeding Torrents?

Bandwidth throttling and traffic shaping are nothing new, but rumors are making the rounds that Comcast is taking it to the next level when it comes to bittorrent traffic.

TorrentFreak claims that Comcast users are finding their torrent uploads throttled whenever they connect to non-Comcast users, which means you can't seed torrents outside the network. It would seem that only seeding peers is being prevented, most users are able to upload to others as long as their download is still going, but once the download is finished the upload is throttled.

Michael mentioned this on Friday and says that he's noticed it getting worse in the last couple of months. I don't have Comcast so I can't say one way or the other. Here's what TorrentFreak has to say:

Unfortunately, these more aggressive throttling methods can't be circumvented by simply enabling encryption in your BitTorrent client. It is reported that Comcast is using an application from Sandvine to throttle BitTorrent traffic. Sandvine breaks every (seed) connection with new peers after a few seconds if it's not a Comcast user.

If you'd like to know more about Sandvine and its somewhat creepy (with regards to net neutrality) goals, have a read through the company's White Paper (PDF link).

A commenter on the TorrentFreak post raises interesting point, with regard to Comcast in particular:

Comcast sells internet access. They also sell video subscriptions, charging extra for on-demand and PPV movies.

If I'm paying to DL a movie from a legal subscription service that uses the bittorrent protocol, and it's blocked, that's anticompetitive behavior designed to get me to use Comcast's services instead of the competitors.

I'm not a lawyer so I can't say for sure if that's the case, but I included it here because it isn't something I've seen brought up before.

It's no secret that ISPs don't like bittorrent or other traffic-clogging peer-to-peer technologies. The ISPs argument runs something like this: just because you pay for a connection at 3mbps doesn't mean you can use whatever protocols you want and potential clog the network for other users by using all 3mbps.

Of course, the natural reaction from many people has been: actually I thought that's exactly what I was paying for. Many users feel the burden of handling the traffic is on the ISPs who, the argument says, need to ensure that the network can handle the traffic.

In an ideal world, I'd tend to agree with that logic, but the truth is most networks simply could not handle the amount of traffic that would result from widespread torrent usage. Which is why ISPs are up in arms about services like Joost or the BBC's new internet video options.

Others would argue that ISPs are a business and are free to charge and shape traffic as they see fit.

It's always a lively debate, so feel free to jump in and have your say. Also if you're a Comcast customer and have seen your torrents throttled let us know about it.