[77663] in North American Network Operators' Group
Re: long as path games?
daemon@ATHENA.MIT.EDU (Joe Provo)
Mon Jan 31 13:23:55 2005
Date: Mon, 31 Jan 2005 13:23:29 -0500
From: Joe Provo <nanog-post@rsuc.gweep.net>
To: nanog@nanog.org
Reply-To: nanog-post@rsuc.gweep.net
In-Reply-To: <BE23ACF5.A464%blaine@blaines.net>
Errors-To: owner-nanog-outgoing@merit.edu
On Mon, Jan 31, 2005 at 09:37:57AM -0800, Blaine Christian wrote:
>
> Specifically, they have the ability to tickle a legacy cisco bug
> with AS path length. This bug was supposedly mitigated in code
> and I believe my previous company is still filtering AS path
> length (UUNET) of 100 or greater.
In recent years there have been issues with memory allocation on
the order of path-length ~50. Similar to bogon filters, it is
recommended to take a survey of sane path lengths before and your
own needs before deploying. Potentially useful data in this
regard is tracked by [suprise] cymru
http://www.cymru.com/BGP/asnpalen01.html
In cisco-land, the max as-length was an undocumented command until
last year or so. a popular value appears to be in the 40-50 range
from folks I know using it.
Cheers,
Joe
--
RSUC / GweepNet / Spunk / FnB / Usenix / SAGE
