To war dial or wardial is to use special software, called a wardialer, to automate telephone connections to a large quantity of telephone numbers. The purpose of wardialing is to identify telephone numbers connected to telephony devices.

For example, if the number dialed is answered by a modem emitting a tone, the wardialer disconnects and saves that number to a log file. The user can try to connect to these phone numbers later using a computer modem, either to investigate the remote systems, or to attempt unauthorized access.

Wardialing gained popular awareness in 1983 after the release of the fictional movie WarGames, where a high school boy discovers a backdoor to a military supercomputer using a wardialer. In the film, the computer used to perform the wardialing is an IMSAI 8080, a kit computer first released in 1975 by IMS Associates.

Security terms, War driving

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