Thank you for this well written document.

Hi Adrian and Suresh, 

The clarifications in the document is needed. Thank you for the effort put into this.

The document is well-written. I appreciate that both the abstract ad introduction make it clear what is being updated. 

I reviewed the document in the past, so I only have very minor comments/nits:

# Positioning the updates

RFC9800 has the following:

   This document updates RFC 8754 by allowing a Segment List entry in
   the Segment Routing Header (SRH) to be either an IPv6 address, as
   specified in RFC 8754, or a REPLACE-CSID container in packed format,
   as specified in this document.

If we had draft-ietf-6man-sidlist-clarification at the time, we wouldn’t need to update 8754. As both 9800 and this present doc will be listed as updating 8754, I wonder whether we can help readers to position the two updates. For example, would it be useful to consider an update to 9800 that would be simply:

OLD:
   This document updates RFC 8754 by allowing a Segment List entry in
   the Segment Routing Header (SRH) to be either an IPv6 address, as
   specified in RFC 8754, or a REPLACE-CSID container in packed format,
   as specified in this document.

NEW:
   This document updates RFC 8754 by allowing a Segment List entry in
   the Segment Routing Header (SRH) to be either an IPv6 address, as
   specified in RFC 8754, or a REPLACE-CSID container in packed format,
   as specified in this document. This use is consistent with RFC-to-be-draft-ietf-6man-sidlist-clarification.

# nit, Section 1

OLD:
   The mechanisms to achieve Segment Routing for IPv6 (SRv6) include the
   use of the Segment Routing Header (SRH) [RFC8754] an IPv6 extension
   header that includes a SID list indicating the sequence of segments
   and any additional processing to be performed.

NEW:
   The mechanisms to achieve Segment Routing for IPv6 (SRv6) include the
   use of the Segment Routing Header (SRH) [RFC8754], an IPv6 extension
   header that includes a SID list indicating the sequence of segments
   and any additional processing to be performed.

Or

NEW2:
   The mechanisms to achieve Segment Routing for IPv6 (SRv6) include the
   use of the Segment Routing Header (SRH) [RFC8754]. The SRH is an IPv6 extension
   header that includes a SID list indicating the sequence of segments
   and any additional processing to be performed.

# Indicate objective of what in this part

CURRENT: 
   The SRH is processed per Section 4 of [RFC8754].  One objective is to
   determine the value to place in the Destination Address field of the
   IPv6 packet.  

# Cite as a reference

(1)

OLD: The figure in Section 2 of RFC 8754 reads:

NEW: The figure in Section 2 of [RFC8754] reads:

(2)

OLD: In describing the HMAC processing, the text in RFC 8754

NEW: In describing the HMAC processing, the text in [RFC8754]

(3)

OLD: packet in RFC 8574 reads

NEW1: packet in [RFC8574] reads

Or

NEW2: packet in Section 5.4 of [RFC8574] reads


# nits: 128-bit or 128 bits

OLD: List are 128 bit entries, but not necessarily IPv6 addresses.

NEW: List are 128-bit entries, but not necessarily IPv6 addresses.

# nit

OLD: List are 128 bit entries, but not necessarily IPv6 addresses.

NEW: List are 128-bit entries, but not necessarily IPv6 addresses.

# Expand HMAC

OLD: HMAC verification checks

NEW: Hashed Message Authentication Code (HMAC) verification checks

Cheers,
Med