CISSP Domain – Cryptography and Security
By Kenneth Magee
There are books upon books about cryptography and this article will not attempt to regurgitate all of the historical background about the subject. However, there are some specific definitions and concepts that you need to understand in order to successfully navigate the CISSP exam and, for that matter, to be successful in your job. First let’s take a look at some definitions: Plaintext — That’s what you’re reading now, plain text. Ciphertext — That’s encrypted text, plain and simple. Encryption — That’s taking a plain text message and converting it to ciphertext. Decryption — That’s taking an encrypted text, or ciphertext, and converting it back to plaintext. Cryptology — Is the science of securing data. Cryptography — Is the process of converting plaintext to ciphertext a.k.a. encryption.