Symmetric Key Example
Let be the plaintext message that Alice wants to secretly transmit to Bob and let be the encryption cipher, where is a secret key. Alice must first transform the plaintext into ciphertext, in order to securely send the message to Bob.
Both Alice and Bob must know the choice of key, or else the ciphertext is useless. Once the message is encrypted as ciphertext, Alice can safely transmit it to Bob (assuming no one else knows the key). In order to read Alice's message, Bob must decrypt the ciphertext using which is known as the decryption cipher, .
Read more about this topic: Ciphertext
Famous quotes containing the word key:
“Power, in Case’s world, meant corporate power. The zaibatsus, the multinationals ..., had ... attained a kind of immortality. You couldn’t kill a zaibatsu by assassinating a dozen key executives; there were others waiting to step up the ladder; assume the vacated position, access the vast banks of corporate memory.”
—William Gibson (b. 1948)