ICMP :
Internet Control Message Protocol. A message control and error-reporting protocol.
IEEE (Institute of Electrical and Electronics Engineers, Inc.) :
A non-profit organization, IEEE is the world's leading professional association for the advancement of technology.
Impedance :
Electrical characteristic of a system or component, expressed in ohms. CCTV industry has standardized 75-ohm impedance.
Infrared (IR) Light :
Invisible light beyond the 750 nanometers(red end of the visible lights).
INT :
Internal sync mode that sets to internal 2:1 interlace.
Intranet :
A private network. It may consist of many LAN and/or WAN.
IP :
Internet Protocol. A set of rules to send and receive messages at the Internet address level.
Iris :
An adjustable opto-mechanical aperture built into a camera that controls the amount of lights coming through the lens.
ISDN :
Integrated Service Digital Network. A set of standard for digital transmission over ordinary telephone copper wire.
Identification :
The act of recognizing one person as being unique from all other people.
Identification Card :
A card that stores the information necessary to verify the identity of the cardholder.
Infrared Light :
Light with a wavelength that is too low to be seen by the human eye.
Infrared Motion Sensor :
A sensing unit that detects motion based on the disruption of infrared light waves.
Input :
An electronic sensor on a controller that detects a change of state in a device outside the controller. See Normally-Closed, Normally-Open.
Insertion Card :
A card that must be inserted into a reader for the reader to retrieve the information stored on the card.
Intelligent Device :
Any type of microprocessor-based input, output, or sensor device that has free-standing logic capability. These devices can be programmed with instructions that allow them to make their own decisions regarding granting access and sounding alarms. They also can communicate with a host computer to receive new instructions or to send event message logs.
