{"id":37246,"date":"2019-05-21T07:00:47","date_gmt":"2019-05-21T04:00:47","guid":{"rendered":"https:\/\/forklog.com\/en\/?p=37246"},"modified":"2025-08-29T14:16:36","modified_gmt":"2025-08-29T11:16:36","slug":"what-is-a-zero-knowledge-proof","status":"publish","type":"post","link":"https:\/\/forklog.com\/en\/what-is-a-zero-knowledge-proof\/","title":{"rendered":"What is a zero-knowledge proof?"},"content":{"rendered":"
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1<\/span><\/p>\n

What is a zero-knowledge proof?<\/strong><\/p>\n

A zero-knowledge proof is a cryptographic protocol that allows one party (the prover) to convince another party (the verifier) that a statement is true without revealing any additional information about it\u2014neither the content nor the source from which the prover learned of its truth. The definition was first proposed by MIT researchers Shafi Goldwasser, Silvio Micali and Charles Rackoff in the 1985 paper The Knowledge Complexity of Interactive Proof Systems<\/a>.<\/div>\n<\/div>\n
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2<\/span><\/p>\n

How does it work? <\/strong><\/p>\n

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Imagine you are in a room with a blindfolded person. On the table lie two balls\u2014one white and one black. You must convince the other person (the verifier) that the balls are of different colours without revealing which is which. \"WhatTo do so, ask them to hide both balls under the table. Then ask them to show just one so you can see it. Next the ball is hidden again and the verifier may show either the white or the black ball. You can prove the claim because you can tell whether they swapped the balls beneath the table.<\/p>\n

Yet the verifier cannot be fully certain, as luck or trickery could still be at play. This is addressed by repeating the experiment n times. With each round the chance of guessing correctly by accident halves: after five repetitions the probability of deception is 1 in 32, after ten rounds\u20141 in 1,024, and after twenty\u2014roughly 1 in 1,000,000.<\/p>\n

Through repetition you can reach the desired level of assurance, though absolute certainty remains unattainable.<\/p>\n<\/div>\n<\/div>\n

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3<\/span><\/p>\n

What is a zero-knowledge proof used for?<\/strong><\/p>\n

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One obvious application in cryptocurrencies is verifying that a user has enough funds for a transaction without revealing to the network who the user is or how much is in the account.<\/p>\n

The protocol can also be used wherever data security is required (for example, for personal information) or for conducting financial transactions.<\/p>\n

A zero-knowledge proof can serve as a tool for verifying data and users, granting privileged access and establishing trusted connections.<\/p>\n<\/div>\n<\/div>\n

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4<\/span><\/p>\n

What types of zero-knowledge proofs exist? <\/strong><\/p>\n

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