The purpose of this article is an analysis of the main concepts related to
the Data Encryption Standard (DES) algorithm and the discussion of two poss
ible low cost implementations. One of them was tested sending messages via
electronic mail.
DES is a 64 bit block cipher for data protection. The algorithm provides a
see of functions on 16 rounds which transform 64 bib of plaintext into 64 b
its of ciphertext. The encrypting process uses a symmetric algorithm. The u
sers select one of the 2(56) possible keys and can change It at any time.
Two implementations of the DES's algorithm are described. The cryptographic
mode selected was apr electronic codebook because, at least initially, it
represented the easiest way to face the design. The software implementation
was developed using C language The hardware implementation is based on Dig
ital Signal Processing (DSP) technology.