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Countersurveillance refers to measures undertaken to prevent surveillance, including covert surveillance. Countersurveillance may include electronic methods such as bug sweeping, the process of detecting surveillance devices, including covert listening devices, visual surveillance devices as well as countersurveillance software to thwart unwanted attempts by cyber crooks to access computing and mobile devices for various nefarious reasons (e.g. theft of financial, personal or corporate data). More often than not, countersurveillance will employ a set of actions (countermeasures) that, when followed, reduce the risk of surveillance. Countersurveillance should not be confused with sousveillance (inverse surveillance) as the latter does not necessarily aim to prevent or reduce surveillance.
Most bugs emit some form of electromagnetic radiation, usually radio waves. The standard counter-measure for bugs is therefore to "sweep" for them with a receiver, looking for the radio emissions. Professional sweeping devices are very expensive. Low-tech sweeping devices are available through amateur electrical magazines, or they may be built from circuit designs on the Internet.
Sweeping is not foolproof. Advanced bugs can be remotely operated to switch on and off, and some even rapidly switch frequencies according to a predetermined pattern in order to make location with sweepers more difficult. A bug that has run out of power may not show up during a sweep, which means that the sweeper will not be alerted to the surveillance. Also some devices have no active parts, an example is the Great Seal given to the US Ambassador to Moscow which hid a device (the Thing).
Amidst concerns over privacy, software countermeasures have emerged to prevent cyber-intrusion, the unauthorized act of spying, snooping, and stealing personally identifiable information or other proprietary assets (e.g. images) through cyberspace.
Most surveillance, and most countersurveillance, involves human rather than electronic methods since people are generally more vulnerable and more capable of reacting creatively to surveillance situations.
Human countermeasures include:
Such activities make it harder to track surveillance subjects. Following steady, easy-to-predict schedules before employing aforementioned countermeasures may make the surveillance detail complacent and thus easier to lose.
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.
The timing of detection surveys and location scans is critical to success, and varies with the type of location being scanned. For permanent facilities, scans and surveys must take place during working hours to detect remotely switchable devices that are turned off during non-working hours to defeat detection.
Instead of transmitting conversations, bugs may record them. Bugs that do not emit radio waves are very difficult to detect, though there are a number of options for detecting such bugs.
Very sensitive equipment could be used to look for magnetic fields, or for the characteristic electrical noise emitted by the computerized technology in digital tape recorders; however, if the place being monitored has many computers, photocopiers, or other pieces of electrical equipment installed, it may become very difficult. Items such as audio recorders can be very difficult to detect using electronic equipment. Most of these items will be discovered through a physical search.
Another method is using very sensitive thermal cameras to detect residual heat of a bug, or power supply, that may be concealed in a wall or ceiling. The device is found by locating a hot spot the device generates that can be detected by the thermal camera.
A method does exist to find hidden recorders, as these typically use a well known frequency for the clock which can never be totally shielded. A combination of existing techniques and resonance sweeps can often pick up even a defunct or "dead" bug in this way by measuring recent changes in the electromagnetic spectrum.
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Technology most commonly used for a bug sweep includes but is not limited to:
In 2011, Defence Minister Peter MacKay authorized a program to search telephone and internet usage for suspicious activities. This program searches for and collects meta-data of Canadians across the country.
There are minimal anti-surveillance movements specifically targeted in Canada at present.
Transparent Lives is a prominent Canadian organization that aims to "demonstrate dramatically just how visible we have all become to myriad organizations and what this means—for better or for worse—for how we conduct our everyday lives." 
Amnesty International runs a campaign called #UnfollowMe that "calls on governments to ban mass surveillance and unlawful intelligence sharing", inspired by Edward Snowden leaking thousands of NSA documents that revealed information about mass surveillance in the U.S. This campaign is active worldwide.
Taken together, the revelations have brought to light a global surveillance system...