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Do Keccak and Poseidon have the same security arguments?

Keccak and Poseidon are both sponge constructions. Keccak’s permutation function is uniquely invertible. This simplifies and strengthens security arguments. Keccak hides 256 bits of internal state when producing an output, so as long as the permutation is chaotic, Keccak is secure. Is Poseidon’s permutation function uniquely invertible? Can you find …

Is there a name for this ‘inverse MOV’ attack and does it work in specialised cases?

The MOV attack works by choosing an elliptic curve with a small embedding degree then using a Tate pairing to map from the curve to a finite field, where the discrete log is sub-exponential. Can you go the other way? Choose an elliptic curve over a small (~ 2^24 ) …

Bulletproofs Question: How does it prove both a proof of knowledge of the vectors and also the innerproduct?

This is about the Bulletproofs zk Proof protocol - https://eprint.iacr.org/2017/1066.pdf (I am going to use additive notation instead of the multiplicative notation used in the paper to describe my question) Prover knows 2 vectors **a** & **b** such that their inner product is c. She creates a binding (but not …

Regev's cryptosystem

Hello, i'm sort of confused by a small point on Regev's pke. Say that the the public parameters is (A, u) = (A, s\^t A + e) with A matrix, s the secret key, e an error. I see that in the original paper as well as in follow up …

PQConnect

Don’t Use Session (Signal Fork)

Looking for HSM opinions

I need to buy an HSM for a project (need it for compliance with government regulations) and I am kind of confused. Price range is really wide. I can see used THALES nCipher HSMs on eBay for as low as 300$ and as high as 10,000$, even though modules are …

Undergrad Research in Cryptography Prerequisites?

Hi, I'm a dual CS & math major. I've been accepted into a mentorship program of sorts and will have the opportunity to do (likely remote) research on a topic (if I find a PI) I'm interested in crypto and have studied the standard intro class to cryptography (classical ciphers …

On The Security Of SHA3 (Keccak)

Hello, I am wondering for any information on the security of SHA3 and its sponge function versus older hash functions like MD5, SHA1, SHA2. What makes it more secure? How heavily studied has it been. The sponge function is still newer than the other constructions but its internal state is …

Use of cryptographic primitives

I was reading this [paper](https://dergipark.org.tr/en/download/article-file/4060550) that claims to "combine metaverse with blockchain", but I have a hard time understanding their use of primitives. On page 4 they first generate the key-pairs (not sure which scheme?): https://preview.redd.it/zpkop4rklife1.png?width=672&format=png&auto=webp&s=8cef80acf6bafc73585f06bb71a8a565fea02afb Then the patient uses his/her private key to sign the data, and then the …