Difference between revisions of "Encryption"

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(Caesar Cipher)
(Caesar Cipher)
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The creator was Julius Caesar.
 
The creator was Julius Caesar.
 
It is a substitution cipher which works by shifting letters by a number. The easiest way to look at a caesar cipher is to think of an inner and outer wheel, each wheel has the letters of the alphabet on its edge. When the letter A on both wheels are aligned the shift is 0 as in the image below:
 
It is a substitution cipher which works by shifting letters by a number. The easiest way to look at a caesar cipher is to think of an inner and outer wheel, each wheel has the letters of the alphabet on its edge. When the letter A on both wheels are aligned the shift is 0 as in the image below:
 +
 +
[[File:Caesar-shift-0.jpg]]
  
 
The shift turns the outer wheel a specific number of spaces. The image below shows a shift of 7:
 
The shift turns the outer wheel a specific number of spaces. The image below shows a shift of 7:
 +
 +
[[File:Caesar-shift-7.jpg]]

Revision as of 19:26, 16 December 2016

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Definitions

Plain text - The data in human readable form.

Cipher - An encryption method or algorithm.

Key - The data used to encrypt or decrypt the plain text.

Cipher text - The encrypted data which can only be understood if decrypted.

Caesar Cipher

The creator was Julius Caesar. It is a substitution cipher which works by shifting letters by a number. The easiest way to look at a caesar cipher is to think of an inner and outer wheel, each wheel has the letters of the alphabet on its edge. When the letter A on both wheels are aligned the shift is 0 as in the image below:

Caesar-shift-0.jpg

The shift turns the outer wheel a specific number of spaces. The image below shows a shift of 7:

Caesar-shift-7.jpg