According to Whitman and Mattord, TEMPEST is a program developed by the United States government to reduce the risk of electromagnetic radiation (EMR) monitoring. (Whitman & Mattord, 2009) Some believe that TEMPEST was actually a code word created by the US government in the 1960s, but was later defined as transient electromagnetic pulse emanation surveillance technology or electronic telecommunications equipment protected from the emanation of spurious transmissions. (Whitman & Mattord, 2009) In general, TEMPEST involves the following types of procedures: ensuring that computers are placed as far away from external perimeters as possible, installing special shielding inside the CPU, and implementing a whole host of other restrictions, including maintaining distance from pipes and other infrastructure components that carry radio waves. (Whitman & Mattord, 2009). The standards and measurements used as part of TEMPEST are contained in a document published by National Security Telecommunications and Information Systems Security. (TEMPEST/1-92, 2008) National Communications Security Committee Directive 4 establishes the U.S. TEMPEST standards. The requirements are set out in NACSIM 5100A, which is classified. TEMPEST certification for private sector use is extremely expensive and, as a result, has led to a newer standard, called ZONE, which is more affordable, if a little less secure. Approved TEMPEST shielded devices are classified into 3 categories. Type 1 is extremely safe and available only to the US government and approved contractors, who must undergo strict controls. Type 2 is a little less safe, but still requires government approval to use. Type 3 is for general commercial use. There are three levels of protection required within the document. The f...... half of the document......nsa.gov/about/faqs/about_nsa.shtmlSANS Institute Information Reading Room. (2011, April 17). Retrieved April 17, 2011, from Sans: http://www.sans.org/reading_room/whitepapers/privacy/introduction-tempest_981McConnell, J.M. (1995, December 12). CRYPTOM. Retrieved April 17, 2011, from NSTISSAM TEMPEST /2-95: http://cryptome.org/tempest-2-95.htmMcConnell, J.M. (2008, September 9). Compromising emanations Laboratory test requirements Electromagnetism. Retrieved April 17, 2011, from NSTISSAM TEMPEST/1-92: http://cryptome.org/nt1-92-6-12.htmOffice, TN (2009, January 15). Information affairs, business and research. Retrieved April 17, 2011, from the National Security Agency's Central Security Service: http://www.nsa.gov/applications/ia/tempest/index.cfmWhitman, M. E., & Mattord, H. J. (2009). Principles of Information Security 3rd ed. Boston: Course Technology.