Unauthorised operation preventions system for unobserved data processing workstation

摘要

A data receiver is associated with a workstation and responds to a signal, possibly encoded. If the signal is not received, a switching unit in the triggers a security circuit for the screen, keyboard and, if required, the mouse.An infrared sensor carried by the user generates an infrared signal contg. a personal code associated with the user which is received by the infrared receiver associated with the screen, keyboard and mouse. The transmitter can transmit the encoded signal in pulses at short intervals, and the security function can be triggered when the pulsed signal has not been received for a small multiple, e.g. 1.5, of the pulse interval, which is of the order of seconds.