[33501] in North American Network Operators' Group
Re: How does one make not playing nice with each other scale? (Was:
daemon@ATHENA.MIT.EDU (Mark Mentovai)
Sat Jan 13 13:29:36 2001
Date: Sat, 13 Jan 2001 13:25:39 -0500 (EST)
From: Mark Mentovai <mark-list@mentovai.com>
To: Paul Vixie <vixie@mfnx.net>
Cc: <nanog@merit.edu>
In-Reply-To: <g3u273nxn0.fsf@redpaul.mfnx.net>
Message-ID: <Pine.GSO.4.31.0101131306050.23844-100000@oak.ggn.net>
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Errors-To: owner-nanog-outgoing@merit.edu
Paul Vixie wrote:
>marcel@our.domaintje.com (Anne Marcel) writes:
>
>> There is no need to deaggregate the /16 that contain nullrouted /32's.
>> This information is (in this case) already available from AS7777 as a
>> multihop eBGP feed.
>
>Nope. No part of ORBS is listed in AS7777. The block which inspired this
>thread is completely private to AS6461 and has to do with that network's AUG.
This sort of brings up an interesting point, though. Has anyone ever
thought about adding a mechanism to BGP for advertising "anti-routes?" -
routes that you can't, don't want to, or won't carry traffic for? In this
case, such a capability could be used to redistribute the 194.178.0.0/16
route from UUNet, and add in a route for !194.178.232.55/32, all without
messy deaggregation. Neighbors would have the option of using this as a
type of automated blackhole avoidance.
There are a few things that would stand in the way of adoption of something
like this: first, each anti-route would require manual configuration, and
that comes with its own set of problems. Another potential issue (this is
purely theoretical, I'm not referring to any past, present, or future
situation in particular) is that providers trying to blackhole a certain
site for AUP violations may want to negatively impact reachability as much
as possible, rather than purely keeping the offending traffic off their
network. These folks wouldn't want to advertise anti-routes because the
resulting blackhole avoidance would encourage others to take working
alternate paths, which does less harm to the site in question.
Still, this may be a beneficial, even if little-used, addition. Thoughts?
Mark
