Re: Can P2P applications learn to play fair on networks?

[Florian Weimer <fw () deneb enyo de>]

* Adrian Chadd:

> So which ISPs have contributed towards more intelligent p2p content
> routing and distribution; stuff which'd play better with their
> networks?

Perhaps Internet2, with its DC++ hubs? 8-P

I think the problem is that better "routing" (Bittorrent content is
*not* routed by the protocol AFAIK) inevitably requires software
changes.  For Bittorrent, you could do something on the tracker side:
You serve .torrent files which contain mostly nodes which are
topologically close to the requesting IP address.  The clients could
remain unchanged.  (If there's some kind of AS database, you could even
mark some nodes as local, so that they only get advertised to nodes
within the same AS.)  However, there's little incentive for others to
use your tracker software.  What's worse, it's even less convenient to
use because it would need a BGP feed.

It's not even obvious if this is going to fix problems.  If
upload-related congestion on the shared media to the customer is the
issue (could be, I don't know), it's unlikely to help to prefer local
nodes.  It could make things even worse because customers in one area
are somewhat likely to be interested in the same data at the same time
(for instance, after watching a movie trailer on local TV).