Customer AS

Avi Freedman freedman at
Mon Aug 19 23:02:54 UTC 1996

> Ah. So this was the automation Sean was referring to - not
> accepting more specifics of routes with identical AS paths.
> telehouse1#conf t
> Enter configuration commands, one per line.  End with CNTL/Z.
> telehouse1(config)#router bgp 5413
> telehouse1(config-router)# neighbor x.x.x.x filter-list 199 in summary-only
> ... Pipedream? I think it would actually be implementatable. I see
> Paul F has managed to get himself on the CC list :-)
> Alex Bligh
> Xara Networks

I thought of building configs to do that (assuming a filter-list xx in summ)
but it's difficult to tell which sets of contiguous BGP announcements are
being announced un-aggregated in an attempt to direct traffic one way or

Without trying to start any religious fights, I would point out that a 
database of what things 'should' look like would be one way to store such
information (about desired/required specificity).

I'll update it this week, but look at for a 
route-aggregation-suggestion tool that I built last year to see "how bad"
the problem was - or, more specifically, how much space could be saved
by taking compressing contiguous routes with the same next-hop (or head
of the AS-Path list, pick which you prefer - they're 95% the same) at
an exchange point.  The page currently has data from April.  Stuff in
>= 207/8 is particularly ugly.


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