3 ms·

Why do you then argue from both sides that no one is proposing lattice only for standardization while simultaneously clearly pushing that it should be lattice o

Why do you then argue from both sides that no one is proposing lattice only for standardization while simultaneously clearly pushing that it should be lattice only? And clearly there is a concern for the lattice only recommendation, even if not officially a standard, being recommended as one. As for why he didn’t advocate for hybrid schemes for 25519, I can’t speak for him. I’m going to guess that it might have something to do with elliptic curve cryptography preceding lattice by 11 years in teens of initial implementation and in more practical terms it’s ahead in terms of research and application by 25-30 years for constructing the algorithms and building solid implementations. Lattice cryptography is fairly nascent and new, with most attention in the past 10-15 years. Both algorithms and implementations have seen significant vulnerabilities discovered. But you know obviously know this which is why it feels to me like you are presenting arguments in bad faith.

tptacek 2mo ago
Lattice cryptography is not in fact fairly nascent. It's new to you, which is not the same thing. That's why I raised the point about 25519's vintage: you're thinking about 25519 in today's context (which, ironically, has taken some of the shine off of it!) and not in the context of 2005, when it was introduced. When TextSecure adopted Curve25519, Bernstein didn't complain and say "you should be doing hybrid triple-FFDH/triple-Curve25519". This is especially useful to know given that mainstream elliptic curve and lattice cryptography are of roughly the same vintage. As commercial propositions, things actually getting fitted into protocols, both date back to the mid-1990s. For a time, there was a question as to whether NTRU might succeed RSA rather than elliptic curves! Nobody's arguing from "both sides". You're continuing to misconstrue what's happening. It's also not true that "nobody is proposing lattice-only". The whole point of this story is that pure MLKEM is a proposal on the table. It has to be, because there are environments that need to use it (that, or not do PQC at all). None of them are environments you're ever likely to work in, and hybrids remain the default and the only PQC KEM standards-track RFC for PQC in development. I'm going to keep pointing out that a lot of the reason you don't have this context is that Bernstein doesn't want you to. He expects you to take his word for it.
- vlovich123 2mo ago
  We seem to be reading different history books. The first elliptic curve paper (1985) precedes the first lattice paper (1996) by 11 years. 2005 is when LWE was published which provided the first theoretical foundation to construct lattice encryption correctly with guaranteed mathematical guarantees. NTRU was plagued with a lot of problems precisely because it lacked this foundation and no one seriously used it or adopted it. 2005 is also when the NSA publicly formalized ECC in its suite B of algorithms and saw widespread standardization across NIST, IEEE, and ANSI. It was fairly well understood how to construct ECC correctly too precisely because it had already been widely studied for like 20 years. So in 2005 you’ve got ECC relying on well known mathematical problems with a solidly understood foundation having been studied for 20 years vs lattice which basically had its first description of how to do lattice. Now maybe if something like Snowden had happened prior, adoption of ECC might have looked differently and the same people would have advocated different things. Hard to tell. But trotting out NTRU like it had any chance in hell with competing with ECC or claiming that ECC and lattice are “basically the same time frame” is just a fundamental disagreement on the facts that isn’t supported by the timelines of each. But sure if lattice truly is resistant to classical attacks you generally don’t lose much from a cryptographic security perspective except that my understanding is it’s still worse on all metrics (compute and size) than ECC. And AFAIK lattice is much more complicated than ECC (both in theory and implementation) - where there’s more complexity there’s more room for mistakes (as the NIST PQ standardization effort demonstrated - very nearly adopted algorithms later proved insecure). ECC by comparison isn’t actually much worse than RSA on that front which again is why no one was proposing dual schemes in 2005,
  - tptacek 2mo ago
    Regev in 2005 was hugely important, but '90s NTRU remains unbroken, and Atjai was 1996. The Suite B thing undercuts your argument! You've managed to establish 25519's publication the same year as Suite B. Again: Bernstein didn't ask people to run 25519/MODP hybrids. I think the bigger thing is that a lot of us are older than we realize, and 2005 was a very long time ago --- over 20 years. This is like the distance between Nevermind and Houses of the Holy. Finally: I'm not letting anybody, including Bernstein, get away with allusions to SIKE as a way of impeaching lattice cryptography. Supersingular isogeny cryptography was moon math, and everybody agreed at the time. It has zero relation to lattice problems. It has zero relation to anything! (Ironically, if it did relate to cryptography in use today, it'd be to elliptic curves).

tptacek 2mo ago

Lattice cryptography is not in fact fairly nascent. It's new to you, which is not the same thing. That's why I raised the point about 25519's vintage: you're thinking about 25519 in today's context (which, ironically, has taken some of the shine off of it!) and not in the context of 2005, when it was introduced. When TextSecure adopted Curve25519, Bernstein didn't complain and say "you should be doing hybrid triple-FFDH/triple-Curve25519". This is especially useful to know given that mainstream elliptic curve and lattice cryptography are of roughly the same vintage. As commercial propositions, things actually getting fitted into protocols, both date back to the mid-1990s. For a time, there was a question as to whether NTRU might succeed RSA rather than elliptic curves! Nobody's arguing from "both sides". You're continuing to misconstrue what's happening. It's also not true that "nobody is proposing lattice-only". The whole point of this story is that pure MLKEM is a proposal on the table. It has to be, because there are environments that need to use it (that, or not do PQC at all). None of them are environments you're ever likely to work in, and hybrids remain the default and the only PQC KEM standards-track RFC for PQC in development. I'm going to keep pointing out that a lot of the reason you don't have this context is that Bernstein doesn't want you to. He expects you to take his word for it.

vlovich123 2mo ago
We seem to be reading different history books. The first elliptic curve paper (1985) precedes the first lattice paper (1996) by 11 years. 2005 is when LWE was published which provided the first theoretical foundation to construct lattice encryption correctly with guaranteed mathematical guarantees. NTRU was plagued with a lot of problems precisely because it lacked this foundation and no one seriously used it or adopted it. 2005 is also when the NSA publicly formalized ECC in its suite B of algorithms and saw widespread standardization across NIST, IEEE, and ANSI. It was fairly well understood how to construct ECC correctly too precisely because it had already been widely studied for like 20 years. So in 2005 you’ve got ECC relying on well known mathematical problems with a solidly understood foundation having been studied for 20 years vs lattice which basically had its first description of how to do lattice. Now maybe if something like Snowden had happened prior, adoption of ECC might have looked differently and the same people would have advocated different things. Hard to tell. But trotting out NTRU like it had any chance in hell with competing with ECC or claiming that ECC and lattice are “basically the same time frame” is just a fundamental disagreement on the facts that isn’t supported by the timelines of each. But sure if lattice truly is resistant to classical attacks you generally don’t lose much from a cryptographic security perspective except that my understanding is it’s still worse on all metrics (compute and size) than ECC. And AFAIK lattice is much more complicated than ECC (both in theory and implementation) - where there’s more complexity there’s more room for mistakes (as the NIST PQ standardization effort demonstrated - very nearly adopted algorithms later proved insecure). ECC by comparison isn’t actually much worse than RSA on that front which again is why no one was proposing dual schemes in 2005,
- tptacek 2mo ago
  Regev in 2005 was hugely important, but '90s NTRU remains unbroken, and Atjai was 1996. The Suite B thing undercuts your argument! You've managed to establish 25519's publication the same year as Suite B. Again: Bernstein didn't ask people to run 25519/MODP hybrids. I think the bigger thing is that a lot of us are older than we realize, and 2005 was a very long time ago --- over 20 years. This is like the distance between Nevermind and Houses of the Holy. Finally: I'm not letting anybody, including Bernstein, get away with allusions to SIKE as a way of impeaching lattice cryptography. Supersingular isogeny cryptography was moon math, and everybody agreed at the time. It has zero relation to lattice problems. It has zero relation to anything! (Ironically, if it did relate to cryptography in use today, it'd be to elliptic curves).