Charlie has arranged a blind date for Alice and Bob, who are both cryptographers, and they...

Charlie has arranged a blind date for Alice and Bob, who are both cryptographers, and they do not know each other before. Charlie also gave Alice and Bob a secret number K (nobody else knows K). Bob wants to make sure that the person he is dating is actually Alice, not somebody else. Please describe how Bob can ask Alice to securely prove that she is Alice (Alice will not reveal the secret number K to anybody). Note that we assume Charlie is a trusted third party and will not run any MITM attack against this blind dating.

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venereology answered 10 months ago

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