How to implement the
Data Encryption Standard (DES)
A step by step tutorial
Version 1.24
The Data Encryption Standard (DES) algorithm, adopted by the U.S.
government in 1977, is a block cipher that transforms 64-bit data
blocks under a 56-bit secret key, by means of permutation and
substitution. It is officially described in FIPS PUB 46. The DES
algorithm is widely used and is still considered reasonably secure.
This is a tutorial designed to be clear and compact, and to provide a
newcomer to the DES with all the necessary information to implement it
himself, without having to track down printed works or wade through C
source code. I welcome any comments.
Matthew Fischer <mfischer@heinous.music.uiowa.edu>