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- Public key - private key question 2 answers
As far as I know, before entities acquire a digital certificate from a CA, their app will generate a pair of keys (PRk and PUk). But what is the private key used for?
P.S. Is user's public key is the same as CA's?
(The reason to ask this is because after CA issues the certificate it will use its private key to do the encryption, but how to decrypt it? )