This definition appears very rarely
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Samples in periodicals archive:
According to a March 2009 Emission Security (EMSEC) Policy issued by the Air Force CTTA, flexible armored cable used in conjunction with Interceptor is an approved PDS solution for CONUS US Air Force, Air National Guard and USAF Reserve bases, as well as off-base government locations operating at SECRET and below and TOP SECRET/SPECAT classification levels.
The Operational Flight Program Combined Test Force (OFP CTF) has outfitted each of its employees at a single workstation with five PC blades on five separate networks to comply with government emission security (EMSEC) requirements for data security, without incurring additional IT support costs.