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1. Zero-Knowledge Proof
1. Also called minimum exposure certificate.

2. Zero-knowledge proof is defined as: the prover can convince the verifier that a certain assertion is correct without providing any useful information to the verifier.

To

Two, application scenarios for understanding:
1. Asymmetric encryption for identity authentication
Scenario: Little A wants to verify whether Little B has a certain private key sk, but Little B does not want Little A to see the private key

Small A uses the public key pk corresponding to the private key to encrypt a piece of data d that only small A knows, and obtains the ciphertext sd;

Little A sends the ciphertext sd to Little B;

Little B uses the private key to unlock the ciphertext sd to get d_new;

Little B sends d_new to Little A;

If d_new == d, then Little A can think that Little B does have the private key sk corresponding to the public key pk.