Subject: Richard Barnes' No Objection on draft-ietf-6man-ext-transmit-04: (with COMMENT)

From: "Richard Barnes" <[email-masked]>
Date: Tue, 08 Oct 2013 08:44:01 -0700

Richard Barnes has entered the following ballot position for
draft-ietf-6man-ext-transmit-04: No Objection

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COMMENT:
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Could you provide any citations on the middle box behaviors, e.g., lack
of support for all of 2460?

10 points to the INT area for the cite to Heller :)

"... Not just a failure to recognize such a header".  
Isn't this another Catch-22?  If a node doesn't recognize a header, how
does it know if it's standard or not?  This also seems in contradiction
to later guidance that unrecognized extensions may be dropped by
default.

A flow chart or pseudo code might be useful in Section 2.1, like "if
(known && standard) { /* policy */ }"

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From: Brian E Carpenter <[email-masked]>
Date: Fri, 11 Oct 2013 16:52:29 +1300

On 09/10/2013 04:44, Richard Barnes wrote:
...
> of support for all of 2460?

The documentation of pretty much any firewall would do it, but that gets
a bit like name-calling. The whole problem came to my attention when a
student discovered that SHIM6 is in practice undeployable across the
Internet unless both hosts are outside all enterprise firewalls.

> to later guidance that unrecognized extensions may be dropped by

I think it's part of the same Catch-22 really; and yes, there's a
problem period after a new extension is defined and before it's
been implemented. Hence the warning at the end of the 3rd paragraph
here: http://tools.ietf.org/html/draft-ietf-6man-ext-transmit-04#section-3

> (known && standard) { /* policy */ }"

Can we keep that for version 2?

    Brian