Network end users to pull down 2 gigabytes a day, continuously?

Alexander Harrowell a.harrowell at
Sun Jan 21 19:41:12 UTC 2007


> > It's a nice idea to collect popularity data at the ISP level, because
> > the decision on what to load into the local torrent servers could be
> > automated.
> Note that collecting popularity data could be done at the edges without
> forcing all tracker requests through a transparent proxy.

Yes. This is my point. It's a good thing to do, but centralising it is an
ungood thing to do, because...

> Once torrent X reaches a certain trigger level of popularity, the
> > local
> > server grabs it and begins serving, and the local-pref function on the
> > clients finds it. Meanwhile, we drink coffee.  However, it's a
> > potential
> > DOS magnet - after all, P2P is really a botnet with a badge.
> I don't see how.  If you detect that N customers are downloading a
> torrent, then having the ISP's peer download that torrent and serve it
> to the customers means you consume 1/N upstream bandwidth.  That's an
> anti-DOS :)

All true. My point is that forcing all tracker requests through a proxy
makes that machine an obvious DDOS target. It's got to have an open
interface to all hosts on your network on one side, and to $world on the
other, and if it goes down, then everyone on your network loses service. And
you're expecting traffic distributed over a large number of IP addresses
because it's a P2P application, so distinguishing normal traffic from a
botnet attack will be hard.

> And the point of a topology-aware P2P client is that it seeks the
> > nearest host, so if you constrain it to the ISP local server only,
> > you're
> > losing part of the point of P2P for no great saving in
> > peering/transit.
> That's why I don't like the idea of transparent proxies for P2P; you can
> get 90% of the effect with 10% of the evilness by setting up sane
> rate-limits.


> As long as they don't interfere with the user's right to choose
> > someone
> > else's content, fine.
> If you're getting it from an STB, well, there may not be a way for users
> to add 3rd party torrents; how many users will be able to figure out how
> to add the torrent URLs (or know where to find said URLs) even if there
> is an option?  Remember, we're talking about Joe Sixpack here, not
> techies.
> You would, however, be able to pick whatever STB you wanted (unless ISPs
> deliberately blocked competitors' services).

Please. Joe has a right to know these things. How long before Joe finds out
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