Subject: Cryptography & Network Security

Topic: Module 2

Difficulty: Medium/High

${\underline{\textbf{Block Cipher & Public Key Cryptography}}}$

Difference between stream & block cipher

1. Stream Ciphers

• In Stream Cipher, encryption & decryption are done on one symbol (such as a character or a bit) at a time.

$P=P_1,P_2,P_3, …..$ $C=C_1C_2C_3…$ $K=(K_1, …