Encryption Policy and the Key-Escrow Controversy Public Key Cryptography Public keys Two mathematically related keys. One used to encrypt a message, the other to decrypt it. Knowing key used to encrypt message no help in decrypting it. Each person has his own key pair, encrypting key can be public-public key. Decrypting is done with the person s private key.
Public keys can be available in directories.
Distributed on Internet free. Digital signatures Public key cryptography lets us sign an electronic copy. The roles of two keys can be reversed. If message is encrypted with private key, can be decrypted with public key from key pair. Provides digital signatures.