[100310] in North American Network Operators' Group
Re: Can P2P applications learn to play fair on networks?
daemon@ATHENA.MIT.EDU (Florian Weimer)
Sun Oct 21 15:27:22 2007
From: Florian Weimer <fw@deneb.enyo.de>
To: eric@spaethco.com
Cc: nanog@merit.edu
Date: Sun, 21 Oct 2007 21:26:16 +0200
In-Reply-To: <471B9757.70005@spaethco.com> (Eric Spaeth's message of "Sun, 21
Oct 2007 13:15:51 -0500")
Errors-To: owner-nanog@merit.edu
* Eric Spaeth:
> Of that group, only DSL doesn't have a common upstream bottleneck
> between the subscriber and head-end.
DSL has got that, too, but it's much more statically allocated and
oversubscription results in different symptoms.
If you've got a cable with 50 wire pairs, and you can run ADSL2+ at 16
Mbps downstream on one pair, you can't expect to get full 800 Mbps
across the whole cable, at least not with run-of-the-mill ADSL2+.
(Actual numbers may be different, but there's a significant problem with
interference when you get closer to theoretical channel limits.)
