Data Encryption Standard (DES)
1 Input is 56 bit key and 64 bit Plain Text”
2 Generate 16 keys 48 bits in length for each
of 16 rounds of scrambling
3 Perform “Initial Permutation” of Data Matrix.
This makes DES more difficult to implement
in software, but does not enhance security.
4 Sixteen rounds of scrambling now occur,
each using a different one of the per-
5 Final Permutation now rearranges the matrix.
6. DES Encrypted Cipher Text
48 bit“Per-Round” KeysK1 - K16
Introduction to Encryption