The Cidr Report

Randy Bush randy at
Mon Dec 2 01:44:00 UTC 1996

> There is no "absolute" point at which to take these measurements. Any
> point will be coloured (colored) by its relative Internet location with
> respect to amounts of local detail and aggregated distant detail.

Yes.  Dave Meyer is trying to overcome this with his new route viewer
(, analogous to Pushpendra's.  He is getting
multi-hop BGP from Europe (thanks RIPE), Japan (thanks IIJ), and MAE-West
(no, LA would probably not be an interesting addition:-) to get widely
disparate and hence interesting views of the infrastructure.

It would be prettier if he could

    ip as-path access-list 142 permit ^NAS_
    route-map peerN-in permit 1
       match as-path 142
       sed-path s/^NAS_//        ! or maybe
       set as-path un-prepend NAS
    neighbor 42.666.7.11 remote-as NAS
    neighbor 42.666.7.11 route-map peerN-in in

to clean the first AS off the path, as it looks tacky.  But I suspect
cisco would fear the impact of such a knob on their support folk.

I do not think this approach would be overly useful for Tony's CIDR
report.  It is not a debugging tool, but an overall trend chart.  The
constant measurement point and relative measure is what I find useful.


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