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Understanding Cryptographic Algorithms
Cryptographic algorithms are used to encode a message from its unencrypted or clear-text state into an encrypted message. The three primary methods of encoding messages are hashing, using symmetric algorithms, and using asymmetric algorithms. The following sections discuss these methods and some of the standards in which they’re used.
The Science of Hashing
As we mentioned earlier, hashing is the process of converting a message, or data, into a numeric value. The numeric value that a hashing process creates is referred to as a hash total or value. Hashing functions are considered either one way or two way.
A one-way hash doesn’t allow a message to be decoded back to the original value. A two-way hash allows a message to be reconstructed from the hash. Most hashing functions are one way. The primary standards that exist that use the hashing process for encryption are as follows: