Unit 2: Basic Cryptographic Concepts
Encryption and decryption of data form the basis of information security. Cryptography is the science of encrypting data. In this unit, we will explore basic cryptography concepts and the purpose of cryptography. Also, we will look into the details of symmetric key encryption techniques. In particular, we will discuss the symmetric key algorithms called Data Encryption Standard (DES), Triple DES, and Advanced Encryption Standard (AES). DES is a block-cipher employing a 56-bit key that operates on 64-bit blocks. Triple-DES is a variant of DES that employs up to three 56-bit keys and makes three encryption/decryption passes over the block. In 1997, NIST initiated a very public, four-and-a-half-year process to develop a new secure cryptosystem for U.S. government applications. The result, the Advanced Encryption Standard, became the official successor to DES in December 2001.
Completing this unit should take you approximately 7 hours.
2.1: Basic Cryptography Concepts: Symmetric Encryption Algorithms
2.2: Purpose of Cryptography
2.3: Data Encryption Standard (DES)
2.4: Triple DES
2.5: Advanced Encryption Standard (AES)