ISPs slowing P2P traffic...

David E. Smith dave at mvn.net
Sun Jan 13 20:02:59 UTC 2008


>It may.  Some of those other things will, too.  I picked 1) and 2) as
>examples where things could actually get busy for long stretches of
>time.

The wireless ISP business is a bit of a special case in this regard, where P2P traffic is especially nasty.

If I have ten customers uploading to a Web site (some photo sharing site, or Web-based email, say), each of whom is maxing out their connection, that's not a problem.

If I have one customer running Limewire or Kazaa or whatever P2P software all the cool kids are running these days, even if he's rate-limited himself to half his connection's maximum upload speec, that often IS a problem.

It's not the bandwidth, it's the number of packets being sent out. One customer, talking to twenty or fifty remote hosts at a time, can "kill" a wireless access point in some instances. All those little tiny packets tie up the AP's radio time, and the other nine customers call and complain.

One customer just downloading stuff, disabling all the upload features in their P2P client of choice, often causes exactly the same problem, as the kids tend to queue up 17 CDs worth of music then leave it running for a week. The software tries its darnedest to find each of those hundreds of different files, downloading little pieces of each of 'em from multiple servers. 

We go out of our way to explain to every customer that P2P software isn't permitted on our network, and when we see it, we shut the customer off until that software is removed. It's not ideal, but given the limitations of wireless technology, it's a necessary compromise. I still have a job, so we must have a few customers who are alright with this limitation on their broadband service.

There's more to bandwidth than just bandwidth.

David Smith
MVN.net



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