CE-408: Cryptography & Network Security SSUET/QR/114
LAB#05
Modern Encryption Techniques
Data Encryption Standard (DES)
OBJECTIVE
The purpose of this lab is to implement DES encryption and decryption in MATLAB.
THEORY
Encryption: It takes 64-bit block of plain text and a 58-bit key as input and produces 64-
bit block of cipher text as output.
Decryption: It takes 64-bit block of cipher text and the same 58-bit key used to produce
that ciphertext as input and produces the original 64-bit block of plaintext.
Refer to the detailed figure for encryption and decryption from the lecture notes.
The reference figures are shown below for encryption and key generation:
Lab#05: Data Encryption Standard (DES) Page | 20
