An implementation of the symmetric-key block encryption. The algorithem was originally invented in 1974 by IBM. Until 2001 DES was widely used around the world and considered extremely secure. Later on was replaced by the AES (the advanced encryption standard). Nowadays Triple-DES (more secured and diffused version of DES) still being used.
As of now, this implementaion takes only a 64-bit maximun message.
http://page.math.tu-berlin.de/~kant/teaching/hess/krypto-ws2006/des.htm
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