How is public key cryptography different?
Public key cryptography is a remarkable solution to this last problem concerning key distribution. There are branches of mathematics, discovered by the scientists named above, that provide for two mathematically related keys where when one key is used to encrypt a message, then only the other one can decrypt the message. And, if only one key is known, it is infeasible for anyone to mathematically derive the other key. Thus, the known key is public, while the other is kept secret and is called the private key. So, how does this work? Suppose everyone who wants to send secure messages to each other creates for themselves one of these key pairs. Each keeps one key private and publishes the other key to everyone else. Each person with a key pair instructs everyone who wants to send a secure message to him to encrypt the message with his public key. When the message is received, this person is the only one who can read the message using his private key, so long as he keeps his private key s
