The 1,800 chips run several times slower than those in a decent home computer, and it cracked the code by using dedicated chips, rather than pure processor speed. More money, Kocher says, could easily make a faster chip, speeding up the process. Previous DES crackers relied principally on software, which takes much more time. Calif. Digital dough. Despite the seeming simplicity of the researchers' attack, cracking DES is extremely taxing on the brains of people and computers alike.
Computers make words, pictures, and answer keys through long strings of zeroes and ones.
Those message bits, when scrambled with the 56-bit answer key, make a seemingly unintelligible message. In the 16 rounds of mixing that follow, the right half is mixed with part of the answer key, then recombined with the left half, and divided again for the next round. Each time, the 32-bit right portion is expanded by 16 bits and mixed with 48 bits of the key. The resultant string of bits, containing both message and key, is divided into eight parts, which are then fed through a series of eight mathematical reference tables that mix and reduce the data, yielding eight 4-bit chunks. They are then mixed with the 32 bits of the left half.