Yes, the one-time pad model provides the technical notion of IND-CPA security. An adversary's advantage at the IND-CPA game is zero if the pad is uniform random. This is a standard—and, once you get past the definitions, trivial!—lemma on the way to proving an IND-CPA security theorem for a pra...
@SqueamishOssifrage Please don't let it bother you when someone votes down such a fine piece of work. It is going to happen, but rest assured that there are others, like me, who are delighted by your witty, brilliant response.
I think there's also some cipher that uses the middle square method for diffusion, but I forget if it was a block cipher or stream cipher or hash. Granted, squaring is not the same as taking a square root, but still. — forestApr 9 at 23:04
Does anyone have any idea what cipher I was thinking of?
@SqueamishOssifrage Oh no it's certainly influential, but not influential enough for the IC to be interested. It's not like the 3GPP, or IETF, or NIST.
Of course, we're certainly monitored for OSINT, like everyone else. :P
@SqueamishOssifrage from looking at the questions tagged with it, I have not been able to infer a meaningful difference from what we would tag anyways as pq-crypto
If its existence bothers you, I suggest you make a Meta Q&A suggesting it to be merged into the pq-crypto tag
The prior thread on Quantum tag reform did not discuss quantum-resistance, and there are many more questions tagged post-quantum-cryptography. The dominant nomenclature seems to be post-quantum, not quantum-resistant—see, e.g., https://pqcrypto.org/, the NIST PQC project, the PQCrypto conference...
I think there's value in a tag for cryptography that is robust of quantum attacks in the "classical cipher" sense, as well as a tag for future constructs. One is a question of robustness and the other is a question of architecture. I see those as related, but exclusive items.
@bdegnan I don't understand the distinction you're drawing. Can you elaborate? Can you show how the distinction figures into any of the tagged questions?
As as physicist, I'm comfortable with wave functions, and the details of quantum devices. We can use these devices to attack certain different structures of an algorithm. I see these attacks as one question as they are not all straight forward. This mainly addresses existing architectures. I see a second question of how to create a construct that robust against known quantum attacks.
That might just be the naive approach, but not being intimately involved in these attacks, that's just how I always have classified things in my head.
I don't see any different between quantum-crypanalysis and quantum-resistance. I see post-quantum-cryptography as what we'll have once we can solidly carry out an attack of a class, which connects to new architectures.
I don't really spent time in these discussions to know what the nuances are of the tags.
It's just the naive physicist reading into what I see thought the assumptions that I make in my own field.
