Rounds of confusion and Diffusion Plaintext Block(64 bits) Key(64 bits) Initial Permutation Strip Parity(56 bits) Round 1 Round 2 Round 16 Reverse Permutation Ciphertext Block(64 bits) 1212 Rounds of Confusion and Diffusion Initial Permutation Strip Parity (56 bits) Key (64 bits) Round 1 Round 2 Round 16 Reverse Permutation Plaintext Block (64 bits) Ciphertext Block (64 bits)