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I'm learning how the Certificate Authority work and have a question.
As my understanding, the Certificate Authority can guarantee that the client get the true public-key:
Saying that I'm a server and you are my client, to ensure that we can communicate securely, we use some asymmetric encryption --- I hold the private-key and I send the public-key to you. Now the problem is that how we can make sure that you get my public-key, instead of someone else's.
In this case, the Certificate Authority can help us: CA encrypts my public-key with its own private-key and send it to you, you use the public-key of CA to decrypt and get my public-key.
If I'm right, my question is:
How can we guarantee that we received the true public-key of CA? In other words, if the thing that I send my public-key to you is not secure, why does the CA sending its public-key to you is secure?