I am an assigned INT directorate reviewer for draft-ietf-6man-hbh-processing. These comments were written primarily for the benefit of the Internet Area Directors. Document editors and shepherd(s) should treat these comments just like they would treat comments from any other IETF contributors and resolve them along with any other Last Call comments that have been received. For more details on the INT Directorate, see https://datatracker.ietf.org/group/intdir/about/.

Based on my review, if I was on the IESG I would ballot this document YES or NO OBJECTION.

I did not find any major issues with the document and it appears to be well written and clear. It modifies the procedures specified in RFC 8200 to make processing of the IPv6 Hop-by-Hop Options header practical with the goal of making these options useful to deploy and use in the Internet.

I did find the following minor issues with this document that should be reviewed and corrected before publication:

- Section 3 defines terminology such as Control Plane. Yet the document uses "Control Plane" and "control plane" (case difference) when it isn't fully clear why the difference. It may be worth reviewing these uses and assure they are correct and intended.

Also, the Control Plane definition should probably say "a router that processes fields" (instead of process)?

Why include "Source"? I didn't find a place where this was used as "Source"? Section 5.2 uses "source"; perhaps it should use "Source" (used multiple times); section 6.1 also uses source (once).

- Section 4.0 - "less than 40B" is a bit cryptic? Perhaps just say "less than 40 bytes" (or 40 octets)?

- Section 5.2.2, why is Option in upper case in first sentence? Perhaps use "Hop-by-Hop option" as I assume you are referring to those options? (Note that section 6 uses "Hop-by-Hop option.)

- Section 6.1, in the third paragraph the first parenthesis is not closed -- likely should be "(e.g., [RFC9268])"?

- Section 7 - are there IANA pages that may need their reference updated from RFC 82000 to this new RFC when published? For example, adding this new RFC to the "Destination Options and Hop-by-Hop Options" description on the https://www.iana.org/assignments/ipv6-parameters/ipv6-parameters.xhtml page? And, adding this RFC to the "IPv6 Hop-by-Hop Option" table entry under "IPv6 Extension Header Types" on that page?

- Section 8:
-- First bullet has "process the a Hop-by-Hop" ... Likely drop the "the"?
-- Third bullet has an extra quote at the end of the sentence.
-- Also, ECMP is used here (first and only time) - perhaps it should be defined or just use "Equal-cost multipath"?
-- The following bullet uses a bit odd wording (change option to options or "limit their" to "limits its")?

   *  The document added restrictions to any future new Hop-by-Hop
      option that limit their size and computational requirements.

- Bernie Volz