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The story is over, I believe everyone has a general impression of the zero-knowledge proof. The essence of zero-knowledge proof is to prove to others that I have a high probability without revealing something that I know or possess (this is very important, after all, zero-knowledge proof is a probabilistic proof). Or own this thing.
The thing to prove in the story is the solution to a Sudoku problem. Xiaoming asked Xiaohong to randomly select rows, columns, and nine-squares of cards each time, and collect them together and randomly scramble them. Xiaohong could not know the solution by opening the bag, but But I can believe that Xiao Ming has a great chance of knowing the solution.
The zk-SNIPM in this story also half-jokingly alludes to the zk-SNARKs (Zero-Knowledge Succinct Non-Interactive Argument of Knowledge) algorithm, which is now the most common zero-knowledge proof. Although the zk-SNIPM in the story has loopholes, it still has room for improvement, such as using a scanner to scan the first combination of cards, and then verify all test sequences at the same time. This makes it difficult to crack the machine through trial and error.
The initial interactive proof method between Xiaoming and Xiaohong alluded to interactive zero-knowledge proof. Interactive zero-knowledge proof requires the verifier (Xiao Ming) to continuously send random trials after the prover (Xiao Ming) puts the answer (commitment). If the verification and certification parties collude in advance, they can simulate/forge a proof without knowing the true answer.
Non-interactive proofs do not require this kind of interaction. However, some additional machines or programs are required, and a series of test sequences are required, which cannot be known by anyone. With such a program and test sequence, the proof machine can automatically calculate a proof and prevent any party from cheating.
Zero-knowledge proof is used in the blockchain encryption currency ZCash, which focuses on anonymity, to ensure the anonymity of both parties to the transaction and the transaction amount. The ZCash team has held two rituals like the story in the story. In the first ceremony, they even shot a documentary. In the second ceremony, a group of people even went to the Chernobyl nuclear accident at any cost to get the The waste of nuclear radiation is then used at high altitude to generate random numbers using nuclear radiation. Those who are interested can go to see the relevant materials of the ZCash ceremony, which is very interesting.