BGP Classful Transport Planes
draft-ietf-idr-bgp-ct-39

Many thanks to Magnus Nyström for his three secdir reviews.

Section 14, para 1:  The 'walled garden' approach is not mentioned anywhere else in the draft.  From the Yoav Nir's secdir review of the idr-bgp-car draft (where similar language was removed):  

    " a) Does the security text provide an adequate description of the formation
     of the "walled garden" via BGP TCP security, address considerations,
     preventing DOS service attacks, and strong BGP security (BGP origin and
     BGPsec).

     b) does the security text provide an adequate description of how to detect
     if traffic goes outside of the "walled garden"? "

# Internet AD comments for draft-ietf-idr-bgp-ct-36
CC @ekline

* comment syntax:
  - https://github.com/mnot/ietf-comments/blob/main/format.md

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## Comments

### S4

* In SR Policy terms, color is a non-zero 32-bit integer (RFC 9256 S2.1).
  Is the Transport Class ID similarly constrained to be non-zero?

  If so, that should probably be state here (in/around the last paragraph,
  perhaps).

  Aha, I see text in S4.3 and S7.9 about zero being reserved for
  "best effort".

  Seems like there could be some text somewhere (anywhere) warning the
  SR-Policy-aware reader of the subtlety here.

## Nits

### S3

* "between SN1 and PE11" ->
  "between SN11 and PE11"

### Appendix C

* "produced by networking industry" ->
  "produced by the networking industry"

### Appendix C.1

* "and SRv6 SID are planned" ->
  "and SRv6 SIDs are planned"

I have been following and reading the draft during its lifecycle in the WG

Thank you to Reese Enghardt for the GENART review.

Thank you for addressing my DISCUSS feedback.

** What’s the experiment to motivate the experimental status?  What does success look like? 

** Section 4.3
   Reserved: 2-octet reserved bits field.
           This field MUST be set to zero on transmission.
           This field SHOULD be ignored on reception, and
           MUST be left unaltered.

Under what circumstances would the Reserved fields NOT be ignored on reception?

Thanks for working on this document. Thanks to Olivier Bonaventure the early TSVART review. Section 11.4 and 11.5 are good addition to this document.