Technical surveillance counter-measures

TSCM (technical surveillance counter-measures) is the original United States Federal government abbreviation denoting the process of bug-sweeping or electronic countersurveillance. It is related to ELINT, SIGINT and electronic countermeasures (ECM).

The United States Department of Defense defines a TSCM survey as a service provided by qualified personnel to detect the presence of technical surveillance devices and hazards and to identify technical security weaknesses that could aid in the conduct of a technical penetration of the surveyed facility. A TSCM survey will provide a professional evaluation of the facility's technical security posture and normally will consist of a thorough visual, electronic, and physical examination in and about the surveyed facility.

This definition is however lacking some of the technical scope involved. COMSEC (communications security), ITSEC (information technology security) and physical security are also a major part of the work in the modern environment. The advent of multimedia devices and remote control technologies allow huge scope for removal of massive amounts of data in very secure environments by the staff employed within, with or without their knowledge.

Technical Surveillance Countermeasures (TSCM) can best be defined as The systematic physical and electronic examination of a designated area by properly trained, qualified and equipped persons in an attempt to discover electronic eavesdropping devices, security hazards or security weaknesses.

Most bugs transmit information, whether data, video, or voice, through the air by using radio waves. The standard counter-measure for bugs of this nature is to search for such an attack with a radio frequency (RF) receiver. Lab and even field-quality receivers are very expensive and a good, working knowledge of RF theory is needed to operate the equipment effectively. Counter-measures like burst transmission and spread spectrum make detection more difficult.

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