how does public key cryptography work

Posted by rap-uvic on Stack Overflow See other posts from Stack Overflow or by rap-uvic
Published on 2010-05-18T00:24:40Z Indexed on 2010/05/18 0:30 UTC
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publickey

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cryptography

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rsa

Hello,

What I understand about RSA is that Alice can create a public and a private key combination, and then send the public key over to Bob. And then afterward Bob can encrypt something using the public key and Alice will use the public and private key combo to decrypt it.

However, how can Alice encrypt something to be sent over to Bob? How would Bob decrypt it? I ask because I'm curious how when I log onto my banking site, my bank sends me data such as my online statements. How does my browser decrypt that information? I don't have the private key.

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