aggregation in 207/8

Avi Freedman freedman at
Tue May 28 22:50:16 UTC 1996

> Is it just me, or does the level of aggregation within 207/8 really suck?
> -- 
> Eric Kozowski             Structured Network Systems, Inc.
> kozowski at   Better, Cheaper, Faster -- pick any two.
> (503)656-3235 FAX         "Providing High Quality, Reliable Internet Service"
> (800)881-0962 Voice       56k to DS1

We see 616 routes in 207/8.

Our route aggregation suggestion tool suggests 281 aggregation possibilities
(which is not 281 routes potentially saved, but 281 routes that could be

It's clear from hand-inspection that some of the routes are being announced
more specifically for multi-homed customers, but I'm sure that a lot of those
routes could be aggregated or are covered by an already-announced more general

Right now, it sorts routes and aggregation suggestions by provider and not 
by IP address, but you can look at:

Some technical & political sisclaimers are on that page :)

One key disclaimer is that it is now sorting by next-hop at MAE-East instead 
of by AS-PATH, but we see a 1:1 correlation in our data between next-AS and

The other key one is that it's a tool that produces interesting output now,
but is NOT designed/tested for generating configs from.


Appear to be some of the most-in-need-of-aggregation areas.

One interesting thing that appears to be the case is that some owners 
(nic-wise) of <= /16s appear to not have a matching catch-all route
and corresponding aggregation installed/announced.


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