dustyharddrive 3 days ago

Anyone have an informed preference between MLKEM and SNTRUP?

  • tptacek 3 days ago

    For what it's worth: Damien Miller has commented repeatedly here that OpenSSH did NTRU before the NIST competition completed, and they always planned to add the NIST PQ winner.

WhyNotHugo 3 days ago

What’s ML-KEM X25519? I’m familiar with Ed25519, but I’ve never heard of ML-KEM.

(Also not a cryptographer)

  • tptacek 3 days ago

    ML-KEM is Kyber, the lattice-based winner of the NIST PQ KEM competition (think of a KEM as a public-key encryption and delivery of a key, as opposed to Diffie Hellman, in which both sides agree on a key together). It's a key establishment mechanism that resists quantum attacks.

    • marcus0x62 3 days ago

      For anyone unfamiliar with the acronyms:

      PQ = Post Quantum (cryptography)

      KEM = Key Encapsulation Method

    • telgareith 2 days ago

      Kyber? For some reason I hear that and think "isn't that the PQ with a foundational Assumption(!) that's been proven trivial for binary computers to break?"

      • zinekeller 2 days ago

        I'm not sure for Kyber, but SIKE/SIDH (another PQ candidate) does have those exact problems (https://eprint.iacr.org/2022/975.pdf)

        • tptacek 2 days ago

          Completely unrelated algorithms; it might be hard to come up with two algorithms less related to each other than module lattices LWE and supersingular isogeny graph Diffie Hellman --- even the outcomes of the two algorithmic approaches are different (SIDH was attractive because it gives you a Diffie Hellman, and Kyber gives you a KEM).

          (I just want to make it clear that this isn't a lingering concern about lattice cryptography, fwiw.)

xyst 2 days ago

look forward to confusing my sysadmins when I present them with a MLKEM pub key :)

Probably will use this on my homelab though.

  • KAMSPioneer 2 days ago

    Your sysadmin will indeed be confused, since ML-KEM public keys are not used for authenticating and are generated by the client and server automatically, analogous to Diffie-Hellman.

    You can confuse them (albeit much less) when OpenSSH adds support for one of the PQ DSAs.