This lesson looks at attack models that are used to test the strength of cryptographic ciphers and hashing, including Ciphertext-only, known-plaintext, chosen-plaintext, chosen-ciphertext, man-in-the-middle, replay, and birthday attacks. Table of Contents: 00:00 - Intro 00:19 - Why Important 00:56 - Cryptographic Attack Models 01:16 - Ciphertext-only Attack 02:09 - Known-plaintext Attack 02:50 - Chosen-plaintext Attack 03:21 - Chosen-ciphertext Attack 04:08 - Hash Attacks 04:27 - Main-in-the-middle Attack 05:13 - Birthday Attacks 07:11 - Replay Attack