Subject: More data on IPv6 Extension Headers

From: Fernando Gont <[email-masked]>
Date: Mon, 03 Mar 2014 10:41:02 -0300

Folks,

Tim and I presented on the topic of IPv6 Extension Header packet drops
at yesterday's IEPG meeting in London.

We used two hacked-on-the-fly slide-decks. Mine is available at:
*
<http://www.iepg.org/2014-03-02-ietf89/fgont-iepg-ietf89-eh-update.pdf>.
(CC to Tim such that he provides an URL for the results he presented).

The interesting slide from my slide-dececk is the graphic which shows
"how many hops away from the intended destination" such packets are dropped.

Having packets being dropped, say, 6-hops from the intended destination
gives some idea that the folk controlling the server may not be the same
folk controlling the packet-dropping device.

The bad news are... well the results we got. The possible good news is
that if we improve the current state of affairs, the figures might be
different in the future.

P.S.: There's certainly much more to do in this area (including "are the
packet-filtering devices ni the same AS as the intended destination?",
etc., etc.). A few of us wll be cooperating on this topic such that we
can provide more comprehensive results, etc.

Thanks!

Best regards,
-- 
Fernando Gont
SI6 Networks
e-mail: [email-masked]
PGP Fingerprint: 6666 31C6 D484 63B2 8FB1 E3C4 AE25 0D55 1D4E 7492

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From: Jen Linkova <[email-masked]>
Date: Mon, 3 Mar 2014 16:43:57 +0100

> folk controlling the packet-dropping device.

Not necessary. As I mentioned on the mic (sorry if my comment was not
clear enough),
the number of hops does not tell us much (as packet might be dropped
on the network edge while the server itself is located few hops away
from it). What would be interesting to see is to compare AS# of the
last working hop and the hop *after* the one where the packet is
dropped.
It would tell you if filtering is happening on the network edge.

-- 
SY, Jen Linkova aka Furry

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From: Simon Perreault <[email-masked]>
Date: Mon, 03 Mar 2014 16:41:38 +0000

> It would tell you if filtering is happening on the network edge. 

+1

In addition, the absolute number of ASes or hops doesn't say much
because it depends on the length of the path. What we need is something
relative to the length. My hypothesis would be that there's not much
being dropped at the 50% mark. It's at the ends that droppage happens.

Simon
-- 
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