Cryptography's Cast
This video presents the same text shown beside it, spoken and on screen. It adds nothing the text does not say.
State
Cryptography's components are a fixed cast: plaintext needing protection, an encryption algorithm and key producing ciphertext, a decryption algorithm and key restoring plaintext for the receiver.
Show
A message crossing a hostile wire unreadable, then readable again at home, used every member.
Watch for
The Unit 3 deferral lands here — cryptography's course home is this strand.