Picture of Secret Messages: Vigenere Cipher
Need to have inter-spy communication? Need to make sure that no one can understand your messages? You need a cipher, specifically a Vigenere Cipher. Created in 1553 by Giovan Battista Bellaso (What an awesome name!) and named after
Blaise de Vigenère (eh) [1]. The Cipher was thought to be indecipherable for almost three centuries[2] and the French even called it "'le chiffre indéchiffrable' (French for 'the indecipherable cipher')" [1].

The Cipher works by combining the numerical values of the letters in the message with the numerical values of the letters in the key.


Remove these adsRemove these ads by Signing Up

Step 1: Your message

Picture of Your message
When you want to send a message you only need two things:

1. Your message
2. The Key- The key should be known by everyone you want to be able to decipher the message. Longer is more secure than short and random letters are more secure than a word. It should also be easy for everyone to remember. 
3. For the first few times you are going to want some scratch paper to work the cipher out on, if you get good you can do it in your head.

My message: Meet at the Statue of Liberty at four on Friday.
My Key: Instructables

Why I picked my key: It is relatively long and it is not a word (in standard dictionaries).

Step 2: Step 1: Misspellings

Picture of Step 1: Misspellings
Warning: Grammar-Nazis, you may want to stop reading here.

This is a very simple step but a one that greatly enhances the security of your message.

Why?: One hundred years ago this wouldn't have been nearly as important but in the age of computers it is significantly more important. By misspelling the words you foil some of the attempts a computer can make at solving the cipher using linguistic patterns.

Before: Meet at the Statue of Liberty at four on Friday
After: Meeet att thee Stattue of Libertea at for on Fryday
Ok, I hope there was nothing too important or interesting in the link, 'cause I'm giving up on decoding it.
Can you cite a source for claiming that Mr. Z used the Vigenere cipher in any form whatsoever?

Your wiki citation is just general information about the unsolved cases. There is no specific mention of any type of cipher at all that I could find, although in the one instance where a zodiac cipher was solved, it was homophonic, not polyalphabetic.
Algag (author)  LittleHairyApe2 years ago
Hm, it appears that I can't find my source> I can't believe that I could have (or would have) made it up. but the article will be changed accordingly. Thanks for the fact check!
That's a fair and honest answer. Thanks for answering my comment. I respect that a lot.
EmcySquare2 years ago
Watch out.
The symbol you used is a Nazi one...
Algag (author)  EmcySquare2 years ago
Problem solved indirectly :)
Actually it's the symbol the zodiac killer used to sign his letters. Although the Celtic Cross has come to be associated with some white supremacist groups in this case it clearly refers to the zodiac and not neo-nazi/whit supremacist leanings.
I visited this site in my confusion...please tell to cipher WHERE THE F%#K I CAN JUST GET TO WHAT I WANT TO SEE!!! oh by the way...nice way of explaining how to cipher Algag...