SIGINT

SIGINT stands for Signals Intelligence, and refers to intelligence-gathering by interception of signals, whether by radio interception or other means.

As sensitive information is often encrypted, SIGINT often involves the use of cryptanalysis. However, traffic analysis[?] can be used to gather information even when the messages themselves cannot be decrypted.

Past and Present SIGINT Activities

• Ultra
• Purple code
• Echelon

Related Topics

• HUMINT - Intelligence gathered by a person on the ground
• IMINT - Intelligence gathered by satellite and aerial photography
• TECHINT - Technical intelligence

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In UNIX-derived operating systems, SIGINT stands for Signal Interrupt or Signal Interactive. It refers to the signal sent to a UNIX process by the kernel when the user on the process's terminal presses Control-C (On some systems, this is the "delete" character).