Re: Do ATM-based Exchange Points make sense anymore?

[cowie () renesys com]

Mike Hughes wrote:
> With the shorter timers or fast-external-fallover, a very short
> maintenance slot at a large exchange can cause ripples in the routing
> table. It would be interesting to do some analysis of this - how far the
> ripples spread from each exchange!

We do BGP instability research, and this is something I'd like to 
examine further.  Compared to other sources of BGP noise, I don't 
think it's a primary driver for the instability we monitor each 
day, but I'd like to quantify it.  

If people were willing to give us a heads-up after the fact when 
there were  .. um .. maintenance events at the major exchanges, 
we could then go back and look at global propagation of the ripples 
on fine timescales.  --jim

p.s. The more eyes we have, the more we see, and we are always looking 
for more silent peers, especially small and midsize providers or their
multihomed customers.  See http://renesys.com/cgi-bin/bgpfeed to 
sign up to send us a one-way multihop EBGP feed.  It's quick, painless, 
and you will be helping unravel the mysteries of why global routing works 
so well in spite of us all.