Questions tagged [schnorr-identification]

The Schnorr Identification Protocol relies upon the security of the Discrete Logarithm Problem. Schnorr's protocol was introduced after, and is comparable to, the identification protocol of Fiat and Shamir and that of Guillou-Quisquater.

39 questions
Filter by
Sorted by
Tagged with
465 views

What's the main difference between the Schnorr identification scheme and its Smart-Card implementation?

This question arises because I couldn't find any official paper for the Schnorr identification scheme, but only for the Smart-Card implementation of it. Also, it seems that everyone, when talking ...
32 views

Domain parameters in the Schnorr identification scheme

I have been recently studying the Schnorr identification scheme. The book Cryptography: Theory and Practice by Stinson and Paterson states the following about the domain parameters in the Schnorr ...
29 views

Congruence in the Schnorr identification scheme

I have been looking at the Cryptography: Theory and Practice book by Stinson and Paterson and when I came to the Schnorr identification scheme, I read the sentence that goes something like this: ...
56 views

Discrete Logarithm Fiat-Shamir Parameters Selection

According to Fiat–Shamir heuristic there are two parameters of the algorithm: big prime number $p$ and primitive root $g$. Thus several questions arise: How big should the prime number $p$ be? How to ...
273 views

Quantitative reduction of Schnorr's identification scheme to DLP

Question I seek a quantitatively better proof of theorem 13.11 in Katz and Lindell's Introduction to Modern Cryptography (3rd edition) (or nearly equivalently, theorem 19.1 in Dan Boneh and Victor ...
84 views

Security proof of schnorr identification scheme

I have studied the Schnorr identification scheme, and I came across the security proof. My question is regarding the following: \begin{align} \text{Pr}\left[\text{DLog}_{\mathcal{A}',\mathcal{G}}\...
40 views

Case Scenarios where Identity Based identification (IBI) Scheme can be employed

I was reading about identity based Identification scheme today. There are lot of articles and research paper on it. There is active research being done in this are of IBI schemes. My question is ...
105 views

Identification Schemes and Internet of Things

I was reading an article titled "A Novel Method for Polar Form of Any Degree of Multivariate Polynomials with Applications in IoT" (doi:10.3390/s19040903) I read the following statement: &...
153 views

Is there any proof for ECDSA signature algorithm?

Related: Is there an interactive version of ECDSA signature protocol like the Schnorr identification protocol?
123 views

Proving equality of two Schnorr Signatures

Given two Schnorr Signatures that were made from the same $x$, where each $x$ is private. Is there a way to prove that they came from the same $x$ without revealing $x$? I heard about Chaum-Pedersen ...
81 views

Does Schnorr identification protocol using commitment scheme?

In schnorr identification protocol, a prover needs to choose a random,let's say $r$ at the beginning, then commit to this randomness as $g^r\bmod p$. When we say "commit", does it really mean we are ...
115 views

Orignal Schnorr Signature vs Discrete logarithmic Schnorr Signature

I have currently started a course on cryptography and am an absolute beginner. While reading through Schnorr's Protocol I came across several ways in which it was described. One of the approach is ...
125 views

Difference between using Schnorr Protocol and just compare hash function to prove knowing something?

I am studying the Schnorr Protocol, and I just come up a case. For example, I am a Prover and have a secret $x$. By using the Schnorr Protocol, I create $h=g^x \bmod p$ and save $h$ to a public place. ...
142 views

602 views

What is difference between an identification scheme and a digital signature scheme?

It seems we can use every identification scheme to sign and verify a message and vice versa. I am right or not? What is difference between an identification scheme and a digital signature scheme?
1k views

Schnorr signature using discrete logarithm / problem with python implementation [closed]

For educational purposes (by purpose with small values for the prime order q), I tried to write a small Python implementation of the Schnorr signature described in the Wikipedia article https://en....
717 views

Schnorr identification protocol security proof

I read about security proof of Schnorr identification protocol against impersonation attack. For the sake of comprehensibility let me sum up the protocol: Given group $G$ with generator $g$. Verifier ...
140 views

The danger of Hash collision in Schnorr NIZK

We use Fiat–Shamir heuristic to turn Schnorr ZK to NIZK. So now NIZK is secure against chosen message attacks in the random oracle model, that is, ideal hash function: every unique query leads to a ...
92 views

Schnorr identification scheme without changing k flaws

The Schnorr identification scheme is being used to remotely log into a home computer which has stored $p$, $α$ and $β(\equiv α^a(mod p))$ - with $a$ the password. This works thusly: 1) The user ...
194 views

Understanding the definition of Schnorrs identification protocol

I have some trouble in understanding the definition of Schnorr's Identification protocol. The is the definition that I received: Prover and verifier agree on a cyclic group $G$ of prime order $q$ ...
255 views

Plausible Deniability in Schnorr

How does a dishonest verifier affect plausible deniability of the interactive Schnorr protocol?
296 views

Security proof of partially blind signature (schnorr signature based)

I read a representative paper about partially blind signature. Abe and Okamoto - "provably secure partially blind signature". They suggested a partially blind signature scheme based on Schnorr ...
1k views

Schnorr protocol: how does malicious verifier win?

My question is about the challenge space size in Schnorr protocol. To be precise, I feel I've read all the Internet (twice) and I still don't understand why is it bad to allow challenge space to be ...
163 views

How we can create a protocol using Schnorr as identification scheme and a hash function as a puzzle?

My question has to do with the creation of a PoWorK( Proof of Work or Knowledge) protocol.How we can create a protocol like this ,using Schnorr as the underlying CVZK protocol and using a hash ...
310 views

Schnorr's identication protocol

Schnorr's identification protocol is said to be a honest verifier zero knowledge protocol. Does it imply it will not work if the verifier is dishonest? I'm wondering if this is the case, it would ...
542 views

Schnorr Identification protocol sometimes wrong?

I'm implementing the Schnorr Identification protocol as part of a larger protocol. In a large percentage of cases, around 20%, my test fails. I don't think it's a code problem, although possible, but ...
Underlying the Schnorr signature is an identification protocol: let $G$ be a cyclic group where discrete log is "hard" and choose $g$ as a generator of $G$. Now have Alice pick a random (secret) ...