EFF DES cracker

In cryptography, the EFF DES cracker (nicknamed "Deep Crack") is a machine built by the Electronic Frontier Foundation (EFF) in 1998, to perform a brute force search of the Data Encryption Standard (DES) cipher's key space – that is, to decrypt an encrypted message by trying every possible key.

Detailed technical data of this machine, including block diagrams, circuit schematics, VHDL source code of the custom chips and its emulator, have all been published in the book Cracking DES.

To avoid the export regulation on cryptography by the US Government, the source code was distributed not in electronic form but as a hardcopy book, of which the open publication is protected by the First Amendment.

[2] Subsequent advances in the price/performance of chips kept reducing that cost until, twenty years later, it became affordable for even a small nonprofit organization such as the EFF to mount a realistic attack.

The first DES Challenge was solved in 96 days by the DESCHALL Project led by Rocke Verser in Loveland, Colorado.

[5] In response to DES Challenge II-2, on July 15, 1998, Deep Crack decrypted a DES-encrypted message after only 56 hours of work, winning $10,000.

Six months later, in response to RSA Security's DES Challenge III, and in collaboration with distributed.net, the EFF used Deep Crack to decrypt another DES-encrypted message, winning another $10,000.