The Cidr Report

On Fri, Nov 12, 2004 at 02:47:30PM -0800, Randy Bush wrote:
> 
> > ASnum    NetsNow NetsAggr  NetGain   % Gain   Description
> > 
> > AS18566      751        6      745    99.2%   CVAD Covad Communications

> are these numbers what i think, but hope not, they are?
> 
> e.g. is AS18566 the origin AS for 751 prefixes that could be
> collapsed to 6?
> 

	Sort of - from here it looks like they aren't actually announcing
the supernets.

>   o and who can hack the perl to generate filters for this
>     so we can listen only to the aggregates
> 

	I don't see their stuff listed in the radb, so it looks like you
have to go to the router itself to read the routes to determine what they
are announcing, then ask the appropriate registry which block they
are announcing from, aggregate the routes in that block, rinse and repeat,
aggregate the aggregated blocks, then filter.
	..but that only works if they announce the supernets. Without that
I'm not sure what you can do that wouldn't end up biting you back. It's also
a lot of work for not too much reward as long as these messes are the
exception and not the rule.

	Plus the public hand slap is kind of amusing. But that's probably
just me.

	Austin