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Cryptography question-how to solve a Ceaser Cipher

  1. Oct 18, 2005 #1
    cryptography question--how to solve a Ceaser Cipher

    yeah, probably a very simple question i know, but we are at a loss of what to do. We havent been given any instruction on how to solve one, but the quest we were given is

    The following message is a Caesar Cipher, a message encrypted by shifting each plaintext letter by a fixed amount:
    Find the deciphering key for this message and decipher the message.

    question is how is this done with out methodically, trial and error, going through the alphabet and subsituting letters over and over again?
  2. jcsd
  3. Oct 19, 2005 #2

    James R

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    One way is to look at letter frequencies. For example, the most common letter in English is 'e', so if you take a long enough ciphertext encoded with the Caesar cipher, the most commonly repeated letter ought to correspond to "e".

    If 'e' doesn't work, try other letters to replace the most common letter, in this order:

  4. Nov 6, 2008 #3
    Re: cryptography question--how to solve a Ceaser Cipher

    Hi there. wow old topic indeed.

    here is the decoded ceaser shift


    The shift was by 5 characters.


    was bored.....
  5. Dec 3, 2010 #4
    Sure! Do a english frequecy counts on the Internet with your letters, get the results, then translate! Good Luck! BlackChamber
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