Thanks Charles. I fixed the nits in the -09 version. 

To answer your question

> 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.

It has a "SHOULD NOT" because ML-KEM-768 could fit in the IKE_SA_INIT depending 
on the rest of the content in the proposal. So strictly speaking, it is not 
certain we would need fragmentation. Additionally, there are networks where IP 
fragmentation is not a problem (reassembly of the fragments succeeds as you 
mention. or where Jumbo Frames are used which could fit all sizes of ML-KEM. 
So, the WG agreed to keep "SHOULD NOT" there as a way to caution implementers 
but not make it completely mandatory. 



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

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----------------------------------------------------------------------
DISCUSS:
----------------------------------------------------------------------

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.


----------------------------------------------------------------------
COMMENT:
----------------------------------------------------------------------

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



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