lecture29: Cryptography and Information Theory

Topics covered

• Secrets
• How to Share a Secret
• Methods for sharing secrets %
• %
• Steganography
• Cryptography
• Crypt\cred{analysis}
• {\color{red Practical Cryptanalysis}}
• We can do better
• Cipher arithmetic
• Better Codes
• Vigen\`{ere Cipher}
• More cryptanalysis
• Block Ciphers
• Letter Pair Cipher ($k=3$)
• More Ciphers