Hello,

I have been selected as the Routing Directorate reviewer for this draft. The Routing Directorate seeks to review all routing or routing-related drafts as they pass through IETF last call and IESG review, and sometimes on special request. The purpose of the review is to provide assistance to the Routing ADs. For more information about the Routing Directorate, please see https://wiki.ietf.org/en/group/rtg/RtgDir

Although these comments are primarily for the use of the Routing ADs, it would be helpful if you could consider them along with any other IETF Last Call comments that you receive, and strive to resolve them through discussion or by updating the draft.

Document: draft-ietf-lsr-isis-sr-vtn-mt-05
Reviewer: Jia He
Review Date: December 10, 2023
IETF LC End Date: date-if-known
Intended Status: Informational 

Summary:
I have read the review comments from Daniele about the concept of enhanced VPN, and the relationship with other existing terms. I agree with his suggestion to follow the discussion and align the draft with the output.
In addition, some minor issues and also nits are found out as follows and should be considered prior to publication.

Minor Issues:
1、In Section 1, it is said "Segment Identifiers (SIDs) can be used to represent both the topological instructions and the set of network resources allocated by network nodes to a VTN." 
Is it "allocated by network nodes" or "allocated to network nodes"? 
If it is "network resources allocated by network nodes", why not "allocated by centralized controllers" as well? 
If it is "network resources allocated to network nodes" which are assocated with a VTN, why not " allocated to network links" as well?
Is there any special consideration by saying "network nodes" only here?

2、In Section 4, "For SRv6 data plane, the SRv6 SIDs associated with the same VTN can be used together to build SRv6 paths with the topological and resource constraints of the VTN taken into consideration." 
Is "SRv6 Locator" missing?


Nits:
1、Section 2, TLV 223 (MT IS Neighbor Attribute) is defined in RFC 5311, which is not referenced in the draft.
2、Section 1,  Paragraph 3, last sentence, s/...need to be distributed using control plane/...need to be distributed using a control plane
3、Section 2, Paragraph 1, last sentecne, s/MT-ID could be used as the identifier of VTN in control plane./MT-ID could be used as the identifier of VTN in the control plane.
4、Section 2, "IS-IS Multi-Topology [RFC5120]" and "IS-IS Multi-Topology Routing (MTR) [RFC5120]" are both used in the draft. It is suggested to keep consistent throughout the draft.