IETF Last Call Review of draft-ietf-lisp-te-21
review-ietf-lisp-te-21-genart-lc-yee-2025-06-14-00

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Document: draft-ietf-lisp-te-21
Reviewer: Peter Yee
Review Date: 2025-06-14
IETF LC End Date: 2025-05-28
IESG Telechat date: 2025-07-10

Summary: Lacking a lot of expertise in this area, I’m not certain that the
issues I list below are correct, but I did find some elements of the document
confusingly written. These may be things that RFC 9300 practitioners understand
easily, but from an outsider’s perspective, I find the document to have minor
issues. [Ready with issues.]

Major issues: None

Minor issues:

Page 6, section 5, 1st paragraph: the sentence says the ELP represents the list
of RTRs, yet it also contains an ETR at the end. Thus, the ELP represents more
than just RTRs. Perhaps changing “represents” to “provides” would do the trick?
Even then, this would contradict the definition of ELP in section 3, which
calls it a list of RTRs and doesn’t say it includes the ETR.

Page 6, section 5, 2nd list item, 2nd sentence: the use of xTRs here seems to
be an expansion of the definition of xTR as given in RFC 9300 so that it now
includes RTRs. That’s fine, but it would be good to highlight the override of
the definition here.

Page 6, section 5, 2nd list item, 4th sentence: this sentence is predicated on
the L-bit being set, in which case the RLOC is x’, not x. Yet the rest of the
list items use x, not x’, which is never used again. While the rest of the list
items could be inferred to refer to x’ instead of x, this isn’t so clear.

Page 15, section 11, last sentence: is the indication of a loop a security
problem or a configuration problem?

Nits/editorial comments:

General:

Capitalize uses of “ipv6” as “IPv6”.

Specific:

Page 3, section 2, 2nd paragraph, 1st sentence: expand the initialisms “ITR”
and “ETR” here as this is their first use in the document.

Page 5, 1st paragraph, second sentence. Terminate the sentence with a period
after “B-->C”. Capitalize the following “one” to start a new sentence. Add
spaces after the individual elements in the list “(X,Y,etr)” for consistency
with most other uses in the draft.

Page 6, section 5, 1st paragraph, 1st sentence: insert “which” before
“represents”.

Page 7, 2nd to last paragraph, last sentence: expand “SDN” as this initialism
is not marked as well-known in the RFC Editor’s acronym list.

Page 8, section 5.1, 2nd paragraph, 1st sentence: change “a” to “an” before
“RLOC”.

Page 8, section 5.2, 1st paragraph, 3rd sentence: change “a” to “an” before
“ELP-based”.

Page 8, section 5.2, 1st paragraph, 4th sentence: consider changing the “to”
before “a private mapping” to “via”.

Page 9, 1st partial paragraph, 1st partial sentence: insert “as” before “the
last”. Move “instead” from before “RTR ‘x’” to after as this just reads better
to me.

Page 9, section 5.3, 1st paragraph, 1st sentence: change “may want to” to
“could”. I don’t think paths have wants.

Page 9, section 5.3, 1st paragraph, 2nd sentence: append a comma after
“congested”. Change “where” to “whereas”.

Page 9, section 5.3, last paragraph: insert “a” before “different”.

Page 10, 1st text paragraph, last sentence: append a comma after “)” and before
“that”.

Page 10, 2nd text paragraph, delete the extraneous space before the final colon.

Page 11, section 6, 1st paragraph, 4th sentence: change “a” to “an” before
“RLOC”. Delete the comma.

Page 11, section 8, 3rd sentence: change “to” to “in” before “the mapping
database”.

Page 11, section 8, 6th sentence: change “which” to “the latter”. Append a
comma after “RTR”. Append “them” after “encapsulates”.

Page 12, section 9, 1st paragraph, 2nd sentence: change “proxy ITR” to
“Proxy-ITR” and “proxy ETR” to “Proxy-ETR” to match RFC 9300 usage.

Page 12, section 9, 2nd paragraph: change “address-family” to “address family”
in two places.

Page 12, section 9, 1st bullet item, 1st sentence: change “are” to “is”.

Page 12, section 9, 1st bullet item, 2nd sentence: consider changing “stretch”
to “expansion”. I couldn’t find much usage of the term “packet stretch”.

Page 12, section 9, 2nd bullet item: change “EID-prefixes” to “EID-Prefixes”.

Page 13, 1st bullet item: change “RLOC-probing” to “RLOC-Probing”.

Page 13, section 10, 2nd paragraph: append “that” after “Note”.

Page 13, section 10, 1st paragraph after the bullet items: prepend a space
before “G”. Consider changing “a” before the resulting “(S-EID, G”) to “an”
depending on how this tuple is read aloud.

Page 14, 1st paragraph, second sentence: append a comma after “That is”.

Page 20, Michael Kowal entry: change “cisco” to “Cisco”.

Page 20, Parantap Lahiri entry: change “Ebay” to “eBay”.