Symmetric Key Algorithms

You already learned about symmetric key ciphers and the major issue with symmetric keys. Read the section in this article on symmetric key encryptions to learn more about the advantages and disadvantages of symmetric keys. There is more information about symmetric key ciphers in this article that will be covered in more detail later in this unit, but this article will give you a preview of 3DES, IDEA, and AES ciphers. View the flashcard tool as well to better understand and to learn the terms used in cryptography such as plaintext, ciphertext, key, encryption, decryption, countermeasure, symmetric key encryption, and block cipher.

2. Cryptography

Cryptography is the enciphering and deciphering of data using various algorithms, and it is a tool that is used to increase the security of a system. The concept of cryptography has been around for a long time and has continued to evolve over thousands of years. One of the first forms of cryptography was used by Julius Creaser, and it is commonly known as the Creaser cipher which was a simple substitution cipher. Modern day cryptography, however, requires much more complicated algorithms in order to serve the purpose of data integrity.

Watch the video, Encryption Part I: Introduction to Encryption 1 (12:15), for an explanation on what encryption is and how it works.