Class action lawyers have sued Comcast for throttling users of the bandwidth-intensive P2P application BitTorrent, and the Federal Communications Commission by a 3-2 vote has declared the cable provider’s practice unlawful. (UPI, Aug. 3; Janko Roettgers, “The FCC Rules Against Comcast. Now What?”, NewTeeVee.com, Aug. 1). But Insight Communications CEO Michael Willner defends the general need for some practice of this sort (Jul. 28; via Class Action Blawg):

[A reader/commenter who has filed a class action suit against Comcast suggests] building whatever capacity needed to give consumers all they use. I’d love to do that but it’s a self defeating process for any ISP with relatively high upload speeds to do so.

Here’s why. My company is accountable to the nearly half million broadband customers on our network. But when we provide relatively high upload speeds (1 meg and better), Internet users all over the world are directed by their P2P software to come to us before they go to slower providers. Within a few days, we simply are unable to handle the load leaving unmanaged consequences to take over, slowing everyone on our network no matter what they are doing. We could add more and more capacity, but the cycle simply starts all over again, bringing even more people to our network for uploads. We never get to the point where we would be able to build enough upload capacity to accommodate everyone from New Zealand to New Brunswick.

So we really only have two choices: We can limit all of our customers’ upload speeds making our network far less attractive to the downloader in New Zealand. That is the net effect of what DSL does. Or we can allocate a disproportionately large amount of upload capacity to our heavy upload users, but limit it fairly.

On some possible technical fixes, see Iljitsch van Beijnum, “IETF: find more peer-to-peer bandwidth, but use it sparingly”, Ars Technica, Aug. 3.