Abstract :
The DES (Data Encryption Standard) algorithm is the most widely used encryption algorithm in the world. For many years, and among many people, to generate "secret code " and DES have been synonymous. DES is a block cipher--meaning it operates on plaintext blocks of a given size (64-bits) and returns ciphertext blocks of the same size. Thus DES results in a permutation among the 2^64 (read this as: "2 to the 64th power") possible arrangements of 64 bits, each of which may be either 0 or 1.