Subject: Benoit Claise's No Objection on draft-ietf-6man-udpzero-06: (with COMMENT)

From: "Benoit Claise" <[email-masked]>
Date: Tue, 09 Oct 2012 13:43:31 -0700

Benoit Claise has entered the following ballot position for
draft-ietf-6man-udpzero-06: No Objection

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COMMENT:
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No objection to the publication of this document, but I really would
like to have the following points clarified.

-  2.  Implementations MUST provide a way to signal the set of ports
          that will be enabled to receive UDP datagrams with a zero
          checksum.

What is an implementation? The application running over the tunnel? You
refer to "An encapsulating protocol" in the sentence before the bullet
points, is this what you mean?
If yes, signal from where to whom?
Or maybe by "implementation" you mean "IPv6 protocol stack
implementation"

- Section 3.1.2  Corruption of the source IP address

Please mention Unicast Reverse Path Forwarding, which might discard
packets.

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From: Magnus Westerlund <[email-masked]>
Date: Wed, 10 Oct 2012 10:23:57 +0200

> for more information about IESG DISCUSS and COMMENT positions.

For a tunnel protocol it is the tunnel protocol implementation that
needs either implicitly or explicitly indicate or signal that it will
use zero checksum for a particular flow or ports.

> Or maybe by "implementation" you mean "IPv6 protocol stack

The protocol or implementation using zero checksum is the one that needs
to signal it. But from my perspective it can be dealt with implicitly in
some cases where static ports works.

Lets try to clarify that formulation.

> Please mention Unicast Reverse Path Forwarding, which might discard

Yes, we can add that as a existing cause for packets with erronous
source address to be dropped.

cheers

Magnus Westerlund

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From: Benoit Claise <[email-masked]>
Date: Wed, 10 Oct 2012 11:18:35 +0200

Hi Magnus,
> Lets try to clarify that formulation.
I would like to see the new text proposal.
Because THE question behind my questions is: how is this requirement 
fulfilled in draft-ietf-6man-udpchecksums-04?

Regards, Benoit.

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From: Stewart Bryant <[email-masked]>
Date: Wed, 10 Oct 2012 12:51:56 +0100

> use zero checksum for a particular flow or ports.
That was a point that I made concerning the text. Are you planning
to add text to the draft(s) to indicate configuration and implicit
signalling are OK?

Stewart

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From: Magnus Westerlund <[email-masked]>
Date: Fri, 12 Oct 2012 10:19:03 +0100

> to add text to the draft(s) to indicate configuration and implicit

I think that is appropriate.

Cheers

Magnus Westerlund