interconnection richness effects Re: Was [Re: Sprint peering policy]

Sat Jun 29 20:01:43 UTC 2002

On Sat, Jun 29, 2002 at 07:42:03PM -0000, Joseph T. Klein wrote:
>
> Flat designs tend to ring like a bell when instability is introduced.
> I think we held the world record for flapping at NAP.NET in 95-96.
> That was a flat design executed during a time when the Cisco architecture
> and software could not keep up with the growth and churn rate. The
> inclusion of algorithms that enhanced oscillation ringing (and since has
> been fixed in IOS) did not help.

Have you ever seen an InterNAP route flap? Its good for around two minutes
or 120 traceroutes of pure humor, with a different loop across a different
backbone in a different city with every invokation.

Extensive peering relationships don't generally cause a breakdown of BGP,
which is probably the reason that we have settled into using that system.
Extensive transit relationships on the other hand, like those used by the 
"optimized routing" crowd to try and take advantage of all the "richness 
of paths" out there which aren't being used efficiently, break BGP very 
very quickly (in my experience at any rate).

-- 
Richard A Steenbergen <ras at e-gerbil.net>       http://www.e-gerbil.net/ras
PGP Key ID: 0x138EA177  (67 29 D7 BC E8 18 3E DA  B2 46 B3 D8 14 36 FE B6)