(Dual Tone Multi-Frequency)

Similar to a password, this series of numbers or letters enables a user to access a system or

These are specific entry points in certain secures areas.  A card reader and monitor switches

ActiveX is Microsoft software component technology, mainly used by Microsoft Windows.

Mutliplexers use this feature, which is a video motion detection technique, to give relay closure for alarms and to improve the update times of video cameras.

(Automatic Gain Control)

(Auto Iris)

When attached to a security camera, an alarm input provides enhanced security in the form of a sensor device, often a door contact or a Passive Infra-red detector for motion detection.  Alarm inputs can be self powered or can require external power (usually 12V).

Some security cameras feature ALC, which means the camera can bring out detail in bright or dark areas of an image.  If too much sunlight makes an image too dark, ALC can focus on the needed image.