the caesar cipher
Post on 18-Jan-2017
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In the 58 D.C. Caesar created the first cipher in the history,
known as the Caesar Cipher.He wanted to comunicate with his contacts
without any external intrusion.
• Caesar shifted the letters in his military commands, following a precise logic.
• Before the comunication begins, he had to determinate this logic with the receiver.
• For example, with a 3 positions exchange, an ‘A’ becomes a ‘D’ , and so on…
• The receiver has to return to the original message with the reverse function.
• After 800 years , Al-Kindi discovered the code breaker for the Caesar Cipher.
• He just analizes the letter’s frequency of a language, idenfying how many times a letter is repeated, in a book for example.
• So, if a crypted message, in that language, has a different frequency, we can discover the shift studying the difference.
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