>In 1975-76, Diffie and Martin Hellman criticized the NBS proposed Data Encryption Standard, largely because its 56-bit key length was too short to prevent Brute-force attack... Their concern was well-founded: subsequent history has shown not only that NSA actively intervened with IBM and NBS to shorten the key size, but also that the short key size enabled exactly the kind of massively parallel key crackers that Hellman and Diffie sketched out. When these were ultimately built outside the classified world, they made it clear that DES was insecure and obsolete. In 2012, a $10,000 commercially available machine can recover a DES key in days.