[IPsec] Charles Eckel's Discuss on draft-ietf-ipsecme-ikev2-mlkem-08: (with DISCUSS and COMMENT)

[Charles Eckel via Datatracker <[e-mail]>]

Charles Eckel has entered the following ballot position for
draft-ietf-ipsecme-ikev2-mlkem-08: Discuss

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DISCUSS:
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I would like to DISCUSS a couple concerns I have with respect to normative
language.

Section 1.2, reads,

"ML-KEM-768 and ML-KEM-1024 public key and ciphertext sizes can exceed the path
MTU; these key exchanges could require more than one IP packet from both the
initiator and the responder."

Section 2.1 says,

"Thus, implementation transporting IKE over UDP and not performing Path MTU
(PMTU) discovery SHOULD NOT use ML-KEM-768 or ML-KEM-1024 in the IKE_SA_INIT
exchange on networks where the PMTU is unknown or restricted."

Why is this not a MUST? How does receiver handle if sender ignores the SHOULD?
I suppose the latter depends on whether reassembly of the fragments succeeds or
not. Is it worth saying something about this?

I also support the DISCUSS by Mahesh on section 2.2.


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COMMENT:
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Thanks to Scott Fluhrer, the document shepherd, for his very helpful write-up,
particularly the insights on IPR claims.

Nits
- Abstract, expand "SA" in "Child SA".
- Section 2.1, s/fields inside it has meaning/fields inside it have meanings