How to tell if something is anycasted?

Edward Lewis Ed.Lewis at
Wed May 17 17:50:46 UTC 2006

At 15:45 -0700 5/16/06, Steve Gibbard wrote:

>The approach I settled on was to ask lots of questions, and then do some
>traceroutes to verify once I knew where to look.  If I knew there was supposed
>to be a server in location x, a looking glass near location x would probably
>find it for me.

 From my experience, passively detecting how something is assembled on 
the Internet has gotten harder with each passing year.  Whether it is 
from intentional obfuscation or just evolutionary new operational 
practices, you can tell a lot less about a set up now that in the 

What Steve says is the right thing to do.  Get off-net ask questions 
and then verify on-net.  Not just for anycasting, for just about 
anything.  The network is a lot less obvious that it used to be.  For 
better or worse, depending on your point of view.

Edward Lewis                                                +1-571-434-5468

Nothin' more exciting than going to the printer to watch the toner drain...

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