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Poly-alphabetic Substitution Cipher

To begin with, the question must be asked, What is Polyalphabetic Substitution?

The name itself sends one's mind spiraling across tiers of "Black boards", which are extremely deteriorated due to them being used for intensive, yet conclusive scientific thinking. To cut a long story short, Polyalphabetic Substitution is a form of cryptography in which, the cipher process consists of replacing or substituting characters with different characters or more than one set of characters. Most ciphers are off this type, so is the Enigma, which is a much more intricate usage of Polyalphabetic ciphers.

Leonne batista Alberti was the first to have realized or invented rather, this method of cryptography in and around 1467. Alberti carried out the encryption process by means of disc's so righteously called, Alberti Discs.

This cipher method of Alberti was simplistic, to say the least, as it consisted of only two discs, no more, no less, of which one was smaller than the other. The smaller disc, inside of the larger one, is allowed to rotate smoothly around the disc's collective central axis. Each disc had letters marked on them and these could be made to coincide exactly with the letters of the other disc. So in order to decipher the given encryption, one has to just know the displacement of the inner disc, relative to the outer disc and apply it. This would give the correct characters corresponding to the coded characters. The method was enhanced over time, to make very complicated ciphers, one such being the Enigma, which consisted of multiple character rotors.

Down The Ages

• Down The Ages Home
• A Hazy Beginning
• The Political Force
  • Key Event: The Babington Plot
  • Key Event: Crypto in Latin America
  • Tools and Devices
    • Vignere Cipher
    • Beale Cipher
    • Poly-Alphabetic Cipher
  • People
• The Wars