UPDATE 2017/09/23: This post has been solved! View the solution here.
Here’s Challenge #5 for September 6, 2017.
A VIGENÈRE CIPHER
In Challenge#2, we featured a Caesar Cipher, the most well-known monoalphabetic substitution cipher. “Monoalphabetic” means that each plaintext letter only has one corresponding ciphertext counterpart.
Today, we’re featuring a Vigenère Cipher, which is the most well-known polyalphabetic cipher. “Polyalphabetic” means that each plaintext letter does not have a one-to-one correspondence with a ciphertext letter. The letter “D” may be enciphered as “H” in one spot and “X” in another.
Here are a few characteristics of my Vigenère:
- It uses the standard English alphabet in the rows and columns. (ABCDEFGHIJKLMNOPQRSTUVWXYZ)
- The key is 10 characters or fewer.
Here’s the ciphertext:
EHAQW DPEZR RWAHT NELTN OHMJE IAWAJ OYNOY HSYPK TGAWW DOJSN SICZY AJRTS ETYHO KRIWO AAPDB FTRAS TRHLZ FHEHT WLBOQ QOYES ECFTZ NOLET DSXFM PETMA
With CodeAWeek.com, I hope to release one cipher, puzzle, or mystery every Wednesday evening. Anyone can attempt to solve. The winner is the first person to send a correct solution and a description of the solve method to firstname.lastname@example.org. Once a correct solution is e-mailed, I will publish a follow-up post, congratulating the winner and revealing the secrets of the code.
You may post questions or theories in the comments, but DO NOT POST SOLUTIONS. E-mail them to email@example.com.
— Tony Youngblood