What Is Encryption

• Encryption is applying a mathematical function to plain text and converting it to an encrypted cipher text.

• A cipher is an algorithm for performing encryption.
  • A cipher usually depends on a piece of auxiliary information called a key.
  • The key, which can vary, changes the detailed operation of the algorithm.
  • A key must be selected before using a cipher to encrypt a message.

• Without the appropriate key, it should be difficult, if not impossible, to decrypt or convert the resulting cipher into readable text.

Why have encryption?

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© 2006 John Michael Pierobon

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