That's a lot of questions.

I'd actually prefer to keep this simple for now: just mark the
algorithms in draft-ietf-ecdhe-mlkem Y and leave the other questions
for later.

-Ekr


On Mon, Feb 23, 2026 at 6:19 AM Bas Westerbaan <bas=
[email protected]> wrote:

> Hey all,
>
> Given store-now/decrypt-later, we should update our recommendations.
>
> I've drafted a quick I-D which we could work on. I couldn't help myself to
> have my preferred outcome as a stub, but it's just a starting point.
>
>
> https://datatracker.ietf.org/doc/draft-westerbaan-tls-keyshare-recommendations/
>
> Now, to actually make progress I see the following questions (if we desire
> to work on this):
>
> 1. Do we want to keep "Y" for quantum vulnerable algorithms? This is
> probably an easy one.
>
> 2. Bit harder: do we discourage ("D") or stay neutral ("N") on quantum
> vulnerable algorithms? Recall that "N" is defined as
>
> Indicates that the item has not been evaluated by the IETF and that the
> IETF has made no statement about the suitability of the associated
> mechanism. This does not necessarily mean that the mechanism is flawed,
> only that no consensus exists. The IETF might have consensus to leave an
> item marked as "N" on the basis of the item having limited applicability or
> usage constraints.
>
>
> Personally I prefer D, but I can live with N if we add a comment.
>
> 3. Which post-quantum key shares do we want to recommend? There is an
> obvious trade off between fragmentation and hindering use cases.
>
> 3a. X25519MLKEM768. Uncontested in adoption at the moment.
>
> 3b. SecP384MLKEM1024. Higher number. Do note that we recommended P384 (at
> the same classical level as MLKEM768) but not P521.
>
> 3c. SecP256MLKEM768. Does it add value next to X25519MLKEM768? There are
> arguments about what FIPS modules or hardware is available today. Is that
> worth a recommendation?
>
> 3d. curveSM2MLKEM768. We did not recommend curveSM2.
>
> 3e. MLKEM{512,768,1024}. Let me cop out here and say we should consider
> this once we actually first adopt a document for it.
>
> My preference is to stick with X25519MLKEM768 for now.
>
> Thoughts?
>
> Best,
>
>  Bas
>
>
>
>
>
>
>
> _______________________________________________
> TLS mailing list -- [email protected]
> To unsubscribe send an email to [email protected]
>
_______________________________________________
TLS mailing list -- [email protected]
To unsubscribe send an email to [email protected]

Reply via email to