Aim: To write a Java program to implement Data Encryption Standard (DES) (only Encryption and key generator) with comment

The main parts of the algorithm are as follows:

Fractioning of the text into 64-bit blocks Initial permutation of blocks

Breakdown of the blocks into two parts:

left and right, named L and R Permutation and substitution steps repeated 16 times

Re-joining of the left and right parts then inverse initial permutation

ALGORITHM:

STEP-1: Read the 64-bit plain text.

STEP-2: Split it into two 32-bit blocks and store it in two different arrays.

STEP-3: Perform XOR operation between these two arrays.

STEP-4: The output obtained is stored as the second 32-bit sequence and the original second 32-bit sequence forms the first part.

STEP-5: Thus the encrypted 64-bit cipher text is obtained in this way. Repeat the same process for the remaining plain text characters