[110058] in North American Network Operators' Group
Re: What is the most standard subnet length on internet
daemon@ATHENA.MIT.EDU (Jon Lewis)
Mon Dec 22 20:11:50 2008
Date: Mon, 22 Dec 2008 20:11:45 -0500 (EST)
From: Jon Lewis <jlewis@lewis.org>
To: Seth Mattinen <sethm@rollernet.us>
In-Reply-To: <49503178.3000304@rollernet.us>
Cc: NANOG list <nanog@nanog.org>
Errors-To: nanog-bounces@nanog.org
On Mon, 22 Dec 2008, Seth Mattinen wrote:
> Anyone running a platform that can't take a full table would apply such a
> filter to weed out anyone who likes to announce all of their space as /24's
> for "traffic engineering". If one does that and doesn't announce the
> aggregate as well, one could find themselves facing random black holes.
There's no "if" about it. Months ago when I and others were looking into
this, we found plenty of examples of networks with /19s, /20s, etc.
announcing only the /24 deaggregates. If you plan to filter these people
and have customers to answer to, you'll need to point default at someone
who's not filtering them.
----------------------------------------------------------------------
Jon Lewis | I route
Senior Network Engineer | therefore you are
Atlantic Net |
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