Using the Vigenere Cipher for Enciphering and Deciphering

In this video I am showing you how to use the Vigenere cipher both to encipher and decipher a message. First described in 1553, and later misattributed to Blaise de Vigenere in the 19th century, for easy encryption and decryption it uses the Vigenere table(also known as the tabula recta), a square containing on each row a letter, followed by the alphabet after it.


To decipher a message you need the key. Go to the line of the first letter in the key and to the right until you meet the first letter of the message, then look at the first letter in it's column. This is the first letter in the message. Repeat with the rest of the message, after the last letter of the key comes the first yet again.


To encipher a message you need to think of a key. Go to the line of the first letter of the key and the column of the first letter of the message, their meeting point being the first letter of the encoded message. Continue the same way with the rest, starting from the beginning of the key when after finishing it.


If you read all of this feel free to comment, I would like to see who is watching.


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