Re: A couple of possibly interesting stats.

[Curtis Villamizar <]

> Looking at how many places the NSFNET sees inbound announcements of
> nets does not matter at all.  All it tells you is that the global
> Internet is redundant in terms of links.
>  
> Look at home ASs of nets - if you aggregate at the home AS, that is
> what is going to count.
>  
> 	--asp@localhost (Andrew Partan)


Andrew,

A lot of the regional networks have more than one attachment point to
ANSnet.  Some use one as primary and one as backup.  Most of the
regional networks announce some of their networks as primary at one
attachment point and other networks at another attachment point.  This
means that that regional could not aggregate before reaching ANSnet
because to do so would mean losing the load balancing.  One longer
term way around this is to have ANS accept more specific routes plus
an aggregate and propogate the more specific routes into it's IBGP but
not propogate them further (just the aggregate).

In any case, configuration is going to get a lot harder for many
regionals to make sure that they aggregate equally to all their peers
but still are capable of passing more specific routes to ANS or any
peer network to which they attach at multiple places and for which
they need to load balance.

Knowing that the average is 2.5:1 just indicates that aggregating
entire AS is not going to be easy and that the figures arrived at
using that assumption are going to be very optimistic at least for the
near term.

The second point I made was that a major role of the routing
arbitrator will be to provide enough knowlege of topology to make more
aggregation possible so we can approach the kind of figures Tony
projected.  Maybe that point got lost because of the way it was
presented.

Regards,

Curtis