# Witness-indistinguishable proof

> Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Witness-indistinguishable_proof
> Markdown URL: https://mediated.wiki/source/Witness-indistinguishable_proof.md
> Source: https://en.wikipedia.org/wiki/Witness-indistinguishable_proof
> Source revision: 1315490503
> License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/)

Variant of a zero-knowledge proof for languages in NP

A **witness-indistinguishable proof** (**WIP**) is a variant of a [zero-knowledge proof](/source/Zero-knowledge_proof) for languages in [NP](/source/NP_(complexity)). In a typical zero-knowledge proof of a statement, the prover will use a **witness** for the statement as input to the protocol, and the verifier will learn nothing other than the truth of the statement. In a WIP, this zero-knowledge condition is weakened, and the only guarantee is that the verifier will not be able to distinguish between provers that use different witnesses. In particular, the protocol may leak information about the set of all witnesses, or even leak the witness that was used when there is only one possible witness.

Witness-indistinguishable proof systems were first introduced by Feige and [Shamir](/source/Adi_Shamir).[1] Unlike zero-knowledge proofs, they remain secure when multiple proofs are being performed in parallel.

## See also

- [Ring signature](/source/Ring_signature)

## References

1. **[^](#cite_ref-1)** Feige, U.; Shamir, A. (1990). "Witness indistinguishable and witness hiding protocols". *Proceedings of the twenty-second annual ACM symposium on Theory of computing - STOC '90*. pp. 416–426. [doi](/source/Doi_(identifier)):[10.1145/100216.100272](https://doi.org/10.1145%2F100216.100272). [ISBN](/source/ISBN_(identifier)) [0897913612](https://en.wikipedia.org/wiki/Special:BookSources/0897913612). [S2CID](/source/S2CID_(identifier)) [11146395](https://api.semanticscholar.org/CorpusID:11146395).

This cryptography-related article is a stub. You can help Wikipedia by adding missing information.

- [v](https://en.wikipedia.org/wiki/Template:Crypto-stub)
- [t](/source/Template_talk%3ACrypto-stub)
- [e](https://en.wikipedia.org/wiki/Special:EditPage/Template:Crypto-stub)

---
Adapted from the Wikipedia article [Witness-indistinguishable proof](https://en.wikipedia.org/wiki/Witness-indistinguishable_proof) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Witness-indistinguishable_proof?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.