Re: long as path games?

[Joe Provo <nanog-post () rsuc gweep net>]

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