Cryptography Part 2: Symmetric Encryption

Today’s approaches to the cryptographic protection of information include symmetric and asymmetric encryption. In this lesson, I describe cryptographic entropy, how symmetric encryption achieves it, and the reason why it is not practical to crack AES encryption. Table of Contents: 00:00 - Intro 00:30 - Cryptographic Entropy 02:40 - Stream Ciphers 06:10 - Block Ciphers 08:03 - Substitution Box (S-Box) 08:49 - Permutation Box (P-Box) 09:18 - Electronic Code Book (ECB) 09:50 - Cipher Block Chaining (CBC) 10:29 - Cipher Feedback Mode (CFB) 11:21 - Counter Cipher Mode (CTR) 11:56 - Kerkhoff's Principle 12:35 - When to use Symmetric Encryption