How to Encode and Decode Using the Vigènere Cipher

The Caesar cipher

Build a cipher wheel as illustrated in Figure 1.1, but with an inner wheel that rotates, and use it to complete the following tasks. (For your convenience, there is a cipher wheel that you can print and cut out at www.math.brown.edu/ / jhs / MathCrypto/CipherWheel. pdf.) (a) Encrypt the following plaintext using a rotation of 11 clockwise. "A page of history is worth a volume of logic." (b) Decrypt the following message, which was encrypted with a rotation of 7 clockwise. AOLYLHYLUVZLJYLAZILAALY

11 Cryptographic Methods That Marked History: From the Caesar Cipher to Enigma Code and Beyond