Chatter is a

signals intelligence Signals intelligence (SIGINT) is intelligence-gathering by interception of ''signals'', whether communications between people (communications intelligence—abbreviated to COMINT) or from electronic signals not directly used in communication ( ...

term, referring to the volume (quantity) of intercepted communications.

Intelligence Intelligence has been defined in many ways: the capacity for abstraction, logic, understanding, self-awareness, learning, emotional knowledge, reasoning, planning, creativity, critical thinking, and problem-solving. More generally, it can b ...

officials, not having better metrics, monitor the volume of communication, to or from suspected parties such as terrorists or spies, to determine whether there is cause for alarm. They refer to the electronic communication as "chatter".Plots, evidence and chatter put U.S. on alert
, ''

CNN CNN (Cable News Network) is a multinational cable news channel headquartered in Atlanta, Georgia, U.S. Founded in 1980 by American media proprietor Ted Turner and Reese Schonfeld as a 24-hour cable news channel, and presently owned by the M ...

'', October 10, 2002. Monitoring chatter is an example of traffic analysis, a sub-field of

.Cheney: More Attacks 'Almost a Certainty'
''

Fox News The Fox News Channel, abbreviated FNC, commonly known as Fox News, and stylized in all caps, is an American multinational conservative cable news television channel based in New York City. It is owned by Fox News Media, which itself is owne ...

'', May 20, 2002. Intelligence specialists hope to learn significant information by methodically monitoring when and with whom suspects communicate. Even if they cannot decrypt what suspects are saying to one another, a change in the volume of traffic may raise alarm, since a large increase may indicate increased preparation for action, while a sudden decrease may indicate the end of planning and the imminence of action. These considerations do not apply when the targets of analysis follow the military practice of maintaining a steady flow of encrypted communications whether they are needed or not.Slowdown in 'chatter' worries officials: Drop in intercepted communication also noticed before 9/11
''

'', August 6, 2008. Some events, including the capture of the "

Algerian Six The Algerian Six were six Algerian men, who gained citizenship of Bosnia and Herzegovina during the Bosnian War, five of whom will continue to hold a dual Algerian and Bosnian citizenship, and who were imprisoned without charges at Guantanamo Bay ...

", were triggered largely by an increase in "chatter".

References

{{Comm-stub Signals intelligence Surveillance