BGP Extensions for BIER
draft-ietf-bier-idr-extensions-19

I do also agree with Roman's discuss..

# Éric Vyncke, INT AD, comments for draft-ietf-bier-idr-extensions-16
CC @evyncke

Thank you for the work put into this document.

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

Special thanks to Ran Chen for the shepherd's (very) short write-up including the WG consensus *but it lacks* the justification of the intended status.

Other thanks to Brian Haberman, the Internet directorate reviewer (at my request), please consider this int-dir review as it contains points to be addressed:
https://datatracker.ietf.org/doc/review-ietf-bier-idr-extensions-16-intdir-telechat-haberman-2024-12-12/ (this review is really recent, but a reply is probably required)

I hope that this review helps to improve the document,

Regards,

-éric


## COMMENTS (non-blocking)

### Abstract and Section 1

Unsure whether BIER is still "new" in 2024... after all RFC 8279 is dated 2017 ;-)

### Section 3

Please add the usual text (MUST be set to 0 and ignored on receipt) about the `Reserved` field.

### Sections 3.1 & 3.2

Please specify the unit for field `Length`.

### Section 8

Suggest using a URI reference https://www.iana.org/assignments/bgp-parameters/bgp-parameters.xhtml#bgp-parameters-2 in addition to the registry name.

What should be the "code" string associated to the TBD new code point ?

As 0 is reserved in the to-be-created registry, should it appear in the list of initial entries ?

## NITS (non-blocking / cosmetic)

### Section 3.3

s/Nexthop is IPv4 address/Nexthop is an IPv4 address/ ? + the same for IPv6

The document has six authors, which exceeds the recommended author limit. Has
the sponsoring AD agreed that this is appropriate?

The IANA review of this document seems to not have concluded yet.

Found terminology that should be reviewed for inclusivity; see
https://www.rfc-editor.org/part2/#inclusive_language for background and more
guidance:

 * Terms "native" and "natively"; alternatives might be "built-in",
   "fundamental", "ingrained", "intrinsic", "original"

Thank you to Behcet Sarikaya for the GENART review.

Thank you for addressing my DISCUSS feedback.

Thanks for the quick work!

Shepherd writeups are valuable to us to summarize certain things we otherwise have to go into in depth.  One that I rely on in particular is the IANA Considerations questions.  Question 20 on the writeup asks the shepherd to review the section and "describe" or "confirm" four specific things, but the writeup only says "Yes".  And the answer to question 21 declares "No new registries" when this document actually does create one.  This leaves me wondering if this was a rushed review.

Do we need Section 10 if Zheng Zhang is also listed as an author/editor?

I'm curious about the SHOULDs in Section 4.  For instance, it seems like we're saying this sub-TLV should be included, but if it's not, there's a default.  Is there any reason not to just go with the default?  Why does this need to be a SHOULD?  Is there a benefit to including the sub-TLV explicitly?