Digital signature with challenge and respond with PQC

Hern

5/23/24, 12:52 PM

Can ECDSA signature signing and verification process replaces password hashed based login system?

The title of this question won't be exactly right.

This is a question that I asked long time ago. I would like to ask does the same application or the underlying mechanism still applicable or is still consider secure when using standardized PQC algorithms that have go through a lot of cryptanalysis?

In such a case, is there a need to really consider a hybrid approach whereby using ED25519,448 along with PQC digital signature algorithms? If an hybrid approach was required, is there any proper ways to do it and what's the recommended PQC algorithms?

0 + 2

post-quantum-cryptography

challenge-response

ed25519

fgrieu

5/23/24, 2:37 PM

The question asks if current Post-Quantum signature schemes can be trusted (in an application where it's signed a challenge for authentication purposes), or if it's needed to additionally use a standard signature scheme (and then how). [This](https://www.ssi.gouv.fr/en/publication/anssi-views-on-the-post-quantum-cryptography-transition/) contains the view of French security authorities. In a nutshell, they recommend _"hybridation"_ at least till 2030.

samuel-lucas6

5/23/24, 3:09 PM

Check out [this](https://soatok.blog/2022/01/27/the-controversy-surrounding-hybrid-cryptography/) blog post for the controversy around hybrid and how to do it. As for recommended algorithms, have a read of the [NIST PQC competition](https://csrc.nist.gov/Projects/post-quantum-cryptography/publications) publications/results and the [BSI recommendations](https://www.bsi.bund.de/EN/Themen/Unternehmen-und-Organisationen/Informationen-und-Empfehlungen/Quantentechnologien-und-Post-Quanten-Kryptografie/quantentechnologien-und-post-quanten-kryptografie_node.html) alongside ANSSI.

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: Digital signature with challenge and respond with PQC

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