Product Cipher

Cryptography and Network Security - Product Cipher

1. CS8792 – Cryptography and Network Security ~ S. Janani , AP/CSE KCET Foundations of Modern Cryptography – Product Cryptosyste m

2. Unit I - Introduction Topic Teaching Aid Activity Security trends - Legal, Ethical and Professional Aspects of Security PPT - Need for Security at Multiple levels, Security Policies PPT - Model of network security, Security attacks, services and mechanism, OSI security architecture PPT Quiz Classical Encryption techniques (Symmetric cipher model, substitution techniques, transposition techniques, steganography) WB Worksheet Foundations of modern cryptography: perfect security, information theory, product cryptosystem, cryptanalysis PPT Worksheet

3. Product Cryptosystems Shannon Combines two or more transformations in a manner intending that the resulting cipher is more secure The product cipher combines a sequence of simple transformations such as substitution (S-box), permutation (P-box), and modular arithmetic.

4. ADFGVX Cipher German Army during World war I PT: COMPUTER KEY: LEMON A D F G V X A D F G V X

5. Intermediate Cipher Text DD AG AF FG GF GD AD AX Transposition by Row – Columnar Matrix KEY : BREAD

6. B R E A D A B D E R X GGDDFGXAFFAGADAD F