Help me make sense of these traceroutes please

Jimmy Hess mysidia at gmail.com
Wed Dec 25 15:28:28 UTC 2013


On Wed, Dec 25, 2013 at 8:03 AM, Martin Hotze <m.hotze at 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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