Des — And 3des

Rearranges the 64 bits of the input block.

Each of the 16 rounds involves expansion, XOR with a subkey, substitution (via S-boxes), and permutation. DES and 3DES

The inverse of the initial permutation to produce the final ciphertext. 2. Triple DES (3DES) Rearranges the 64 bits of the input block

Developed in the 1970s, DES was the global standard for decades before its 56-bit key became vulnerable to modern brute-force attacks. XOR with a subkey