Subject: [pim] Éric Vyncke's No Objection on draft-ietf-pim-igmp-mld-extension-06: (with COMMENT)

From: Éric Vyncke via Datatracker <[email-masked]>
Date: Mon, 31 Jan 2022 06:48:35 -0800

Éric Vyncke has entered the following ballot position for
draft-ietf-pim-igmp-mld-extension-06: No Objection

When responding, please keep the subject line intact and reply to all
email addresses included in the To and CC lines. (Feel free to cut this
introductory paragraph, however.)

Please refer to https://www.ietf.org/blog/handling-iesg-ballot-positions/
for more information about how to handle DISCUSS and COMMENT positions.

The document, along with other ballot positions, can be found here:
https://datatracker.ietf.org/doc/draft-ietf-pim-igmp-mld-extension/

----------------------------------------------------------------------
COMMENT:
----------------------------------------------------------------------

Thank you for the work put into this document. The mechanism is simple and
powerful; the document is also easy to read.

Please find below some non-blocking COMMENT points (but replies would be
appreciated even if only for my own education).

Please also have a look at Tommy Pauly's INT directorate review at
<https://datatracker.ietf.org/doc/review-ietf-pim-igmp-mld-extension-05-intdir-telechat-pauly-2022-01-20/>.

Special thanks to Mike McBride for the shepherd's write-up including the
section about the WG consensus.

I hope that this helps to improve the document,

Regards,

-éric

# Section 3

It is unclear to me what to do when more TLV should be sent than allowed by the
MTU. May/should/may not different subset of TLVs be sent over multiple packets
(à la IPv6 Router Advertisement) ?

## Section 3.1

I was about to raise a DISCUSS on this issue. It appears that the E-bit is
specified in this document while it was defined as reserved in MLDv2 RFC 3810,
i.e., should this document formally update RFC 3810 (and possibly IGMPv3 as
well)? I.e., in the header + abstract + introduction ?

Also, does this mean that once the E-bit is set, then there cannot be any other
extensions except TLVs ? This seems a limiting factor.

## Section 6

Indeed, a lot of small TLVs could increase the cost of processing, hence be an
element of attack; but I would expect from an I-D to have some mitigation
proposals.