“Then Alice uses that key to encipher her message and when she’s done, she sends this message to Bob. This is how email works.” He drew an arrow going from Alice to Bob with “message” written above it.
“In this case, if anyone is able to intercept the message, they will just see the enciphered version, what we call ciphertext. It will look like nonsense, like this—“ He started writing what seemed like random letters, five at a time with spaces in between. Sara looked carefully. J.D. had written: “RWMUW XTPIY GTSPN PPEZ”
“And when the message gets to Bob, he uses his key to decipher the message. He can now read Alice’s message. The person who intercepted the message did not know what Alice told Bob. The pictures on the board helped Sara understand what he had explained.
Devil's Fork Page 28
