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Re: Help me make sense of these traceroutes please


From: Jimmy Hess <mysidia () gmail com>
Date: Wed, 25 Dec 2013 09:28:28 -0600

On Wed, Dec 25, 2013 at 8:03 AM, Martin Hotze <m.hotze () hotze com> wrote:

On 2013-12-25 00:16, Sam Moats wrote:

...

You are likely seeing the effects of asymmetric routing.
. .. or the effect of passing traffic through NSA infrastructure.


Ah... NSA.   That's probably it.
So much for my theory of a Router virtual chassis  straddling  the atlantic.

 or the extra kinetic energy carried by the overseas-bound packet took
longer for the router to absorb and rebound with an ICMP.





But in all seriousness --- what is probably happening here, is  the result
of extra  "hops"  that don't show up in  traceroute.
MPLS tunnels could well fit the bill.



Other things to consider when latency seems sensitive to destination IP ---
are preceding device in the traceroute might also have multiple links to
the same device;  with one link congested and some form of IP-based load
sharing,  that happens to be the toward-overseas link.



SCNR, #m

-- 
-JH


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