Of prime concern to the U.S. Department of Homeland Security is the Information Technology security of the digital control systems used in industries considered to be part of the critical infrastructures. Such industries include electric utilities, petroleum, water, waste, chemicals, pharmaceuticals, pulp and paper, and metals and mining. The Process Control Security Requirements Forum (PCSRF), a working group of organizations from various sectors that comprise the U.S. Process Control Systems, is also concerned about the security of digital control systems. Therefore, the PCSRF collaborates with security professionals to assess the vulnerabilities of the critical infrastructure systems and to establish appropriate recovery strategies and countermeasures for dealing with terrorist and cyberterrorist attacks. The objective, of course, is to keep the risk of a cyber Apocalypse to an acceptable level. Falco, J., Stouffer, K., Wavering, A., and Proctor, F. IT Security for Industrial Control Systems. [Online, 2004.] National Institute of Standards and Technology Website. http://www.isd.mel.nist.gov/documents/falco/ITSecurityProcess.pdf.