Rju Tsq Sz Koxjuhm: The Multiplication Cipher

Cipher cracking is food for the brain. Often when you give kids a cipher puzzle, and you’ll struggle to get them to stop cracking them. In groups they will talk, and share ideas, and then the work together to solve them. There’s something magical about taking something that is secret and discovering it. So let’s do a little bit of cipher creation.

Let’s what Caesar wants to send a secret message to Cleoptra, and doesn’t want Mark Antony to read the message. For this Caeser could use a shifted alphabet cipher, and where he moves the letters by three places to the right:

In this case a cipher of KHOOR is deciphered as “hello”. Unfortunately this is not a strong cipher as there are only 25 valid ciphers, and it would be thus easy for Mark Antony to crack it. An improved method is then to scramble the alphabet:

In this case the message that Caesar sends is “LQNZDOO”, and which is “inkwell”. The good thing with this cipher is that there are 26! different combinations, so it would take…