How to tell if something is anycasted?

Edward B. DREGER eddy+public+spam at
Wed May 17 05:07:34 UTC 2006

DH> Date: Tue, 16 May 2006 18:05:10 -0400
DH> From: David Hubbard

DH> So I'm looking at a company who offers anycasted DNS;
DH> how do I tell if it's really anycasted?  Just hop on
DH> different route servers to see if I can find different
DH> AS paths and then do traceroutes to see if they suggest
DH> the packets are not ending in the same location?

More or less.  Latency triangulation actually is useful in this
instance, too. :-)

DH> From my routers' perspective I don't see a difference, but then
DH> I don't think I should, correct?

Think of it as multihoming, only the end "node" is geographically
distributed.  The "node" may also lack "interior" routing.

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