This work is sponsored by the US Department of Energy Office of Science and the National Science foundation under grants STI-0334088 and NRT-0335290. Special thanks to Vern Paxson, Brian Tierney, Matthias Vallentin, and Mark Dedlow for help on the Bro cluster.
Parts of this work were produced under the auspices of the Institute for Information Infrastructure Protection (I3P) research program. The I3P is managed by Dartmouth College, and supported under Award number 2003-TK-TX-0003 from the U.S. Department of Homeland Security, Science and Technology Directorate. Points of view in this document are those of the author(s) and do not necessarily represent the official position of the U.S. Department of Homeland Security, the Science and Technology Directorate, the I3P, or Dartmouth College.