Re: FYI: DNSOPS presentation

[Tore Anderson <tore.anderson@redpill-linpro.com>]

Hi Mark,

* Mark Andrews

> The first thing is to publish a complete description of the testing 
> methodology and envionment.  So far I havn't see it.

I've posted descriptions a couple of times before:

http://lists.cluenet.de/pipermail/ipv6-ops/2009-November/002658.html
http://www.ietf.org/mail-archive/web/dnsop/current/msg08406.html

Have a look, and don't hesitate to let me know if you're still wondering
about something.

> Most of the transition technology involves encapsulation so was the
> mtu set to prevent pmtud being triggered due to encapsulation in
> IPv4?

I haven't set the MTU explicitly, but the objects that are being served
are (intentionally) very small, so I never transmit any packets that are
anywhere near 1280 octets.  However I see that I occasionally receive
incoming packets that exceed 1280 (HTTP requests with large amounts of
header information).  I will try to reduce the advertised TCP MSS to
prevent PMTUD in the inbound direction from ever becoming an issue.
These jumbo requests occur very seldom though, so I'll be very surprised
if the lowered MSS will make a noticeable impact on the measured client
loss.

Thank you for your feedback!

BR,
-- 
Tore Anderson
Redpill Linpro AS - http://www.redpill-linpro.com/
Tel: +47 21 54 41 27