RC4 is a symmetric encryption algorithm designed in 1987 by Ron Rivest, Adi Shamir and Adleman. It uses a stream cipher for encryption that randomly generates a keystream of bits used to encrypt the plaintext. The algorithm uses a variable keysize between 40 to 2048 bits to generate a pseudo-random permutation that is combined with the plaintext.

1. RC4 Algorithm

2. Introduction
• RC4 designed in 1947
• By RSA (Ron Rivest, Adi Shamir, Adleman
• Symmetric Encryption
• Stream Cipher

3. RC4 Block Diagram