GPU vs. CPU Supercomputing Security Shootout, by Collin Brack. There was no debating the facts and figures Brack showed the audience illustrating the processing power of multi-processor GPGPU (General Purpose Graphics Processing Unit) technology over the processing power of the general purpose CPU. For certain computational tasks, low cost, high performance GPU technology has found its way into the world of supercomputing and the information security industry. After a brief mention about Nvidia’s CUDA versus competing GPU technologies from ATI and OpenCL, Brack presented GPU verus CPU benchmarks of security tools including aircrack (10x speed-up), Pyrit (8x), CUDA Multiforcer, BarsWF MD5 cracker (3x), RainbowCrack multi-GPU CUDA version, and others. Brack emphasized results obtained with Pyrit, a GPU cracker for attacking WPA/WPA2 PSK protocols. Sometime before ShmooCon 2010, Brack had submitted code modifications to the Pyrit svn. Using Pyrit 0.2.5-svn r208 on his MacBook Pro Core 2 Duo 2 2.5Ghz computer with precomputed tables, Brack recorded the results at about 300,000 keys per second; with his code modifications in Pyrit r209, Brack achieved about 1,000,000 keys per second. With more than three times greater performance, Pyrit r209 seems like a viable alternative.