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Questions tagged [zero-knowledge-proofs]

Zero-knowledge proofs are an interactive method for one party to prove to another that a statement is true, without revealing anything other than the veracity of the statement.

Zero-knowledge proofs are an interactive method for one party to prove to another that a statement is true, without revealing anything other than the veracity of the statement.

Wikipedia: Zero-knowledge proof

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How do I explain zero knowledge proof to my 7 year old cousin?

How do I explain zero knowledge proof to my 7 year old cousin?
Nathan Aw
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What is a Non-Interactive Zero Knowledge Proof?

I understand the concept of a Zero Knowledge Proof thanks to the easy to understand analogy of Alibaba's cave. However, this seems to require interaction between the verifier and the other party. I have not found an explanation of non-interactive…
BBedit
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Is a hash a zero-knowledge proof?

I’m trying to wrap my head around zero knowledge proofs, but I’m having trouble understanding it. In my current understanding, zero-knowledge proofs prove to the recipient that the sender has a certain knowledge without disclosing it. Like trying to…
vrwim
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Why are zk-SNARKs possible, in layman's terms

zk-SNARK: Zero-Knowledge Succinct Non-interactive Argument of Knowledge From the Ethereum blog: One natural use case for the technology is in identity systems. For example, suppose that you want to prove to a system that you are (i) a citizen of a…
bkoodaa
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When would one prefer a proof of knowledge instead of a zero-knowledge proof?

I've just realized I find it hard to distinguish between these two terms (proof of knowledge, and zero-knowledge proof), specially where only the latter seems to be used in many cryptographic protocols. Zero-knowledge proofs are usually defined as…
LRM
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Is Using Digital Signatures to prove identity a zero knowledge proof?

Suppose Alice publishes a book with a public key in it, and later wants to prove that she wrote the book. She could sign challenge messages with her private key, and others could verify those signed messages. Alice is proving she knows a private key…
Scott Driscoll
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What are zk-STARK's?

The zk-STARK is a proof zero-knowledge proof system that, in contrast to the zk-SNARK, no longer relies on a trusted setup where the "toxic waste" parameters are initialized. What are, in layman's terms, the basic building blocks of the zk-STARK,…
CRYPTONEWBIE
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How does the simulator of the special-honest verifier zero-knowledge property works?

I’m a bit confused about what the simulator of the special-honest verifier zero-knowledge property of a $\Sigma$-protocol is supposed/allowed to do and how to prove that it is indeed efficient (i.e. it runs in a time polynomial in the security…
LRM
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How do zero knowledge protocol with vertex-3-coloring work?

I'm currently not sure if I understood how the zero knowledge protocol with vertex-3-coloring works. I'll describe what I think I've understood and I'll write my questions in bold. Zero-knowledge-protocols in general What are they good for? What is…
Martin Thoma
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Zero-knowledge proof system which is not proof of knowledge?

I have learned that a zero-knowledge (ZK) proof system can be constructed by making use of the three-color problem. In this particular case, the proof system also happens to be proof of knowledge (POK), i.e. any prover necessarily needs to know a…
dkaeae
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Why Victor must not know which tunnel Peggy chooses?

In the classic description of Zero Knowledge Proof of Knowledge, Victor must wait outside the entrance to the cave while Peggy goes to the fork and choose a side. It's only once Peggy has entered a tunnel and is out of view that Victor comes at the…
Yolanda Ruiz
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Practical consequences of a honest-verifier zero-knowledge of the Schnorr protocol

Schnorr protocol is known to be honest-verifier zero-knowledge and not perfectly zero-knowledge. What are the practical consequences of this fact? Does it mean a dishonest verifier can do something to discover the secret exponent $x$? Setup $P$…
omnomnom
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Converting to rank one constraint system (R1CS)

I was reading Vitalik Buterin's post$^\color{magenta}{\star}$ on ZK-snarks and I need some clarification on some points. Since there aren't that many posts and articles on the subject, I had no choice other than turning to Stack Exchange . First, I…
Hesaam
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Can I construct a zero-knowledge proof that I solved a Project Euler problem?

Is there a practical method, and if so what is the method, to reveal that I have the following type of answer but conceal the answer itself? The answer is, let's say, the solution to a Project Euler problem. That is all. However, I'm new here. I'll…
minopret
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Zero-knowledge proof using quadratic residue: why two options?

In the zero knowledge proof using QR, why do we even bother with the server sending us $b = 0$ back? As I understand it, the server selects $b = 0$ or $b = 1$. If $b = 0$, then the client (Alice) generates a random number $r$ and sends back $r^2…
healthycola
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