A computer network in which processing and control functions are performed at several levels by computers specially suited for the functions performed, such as industrial process control, inventory control, database control, or hospital automation.

Routing that is based on hierarchical addressing.
Note: Most Transmission Control Protocol/Internet Protocol (TCP/IP) routing is based on a two-level hierarchical routing in which an IP address is divided into a network portion and a host portion. Gateways use only the network portion until an IP datagram reaches a gateway that can deliver it directly. Additional levels of hierarchical routing… (Read More →)

A mutually synchronized network in which some clocks exert more control than others, the network operating frequency being a weighted mean of the natural frequencies of the population of clocks.

Frequencies from 3 MHz to 30 MHz. See electromagnetic spectrum.

With reference to American National Standard ANSI T1.631-1993, an aspect of National Security and Emergency Preparedness (NS/EP) telephone calls, as implemented in the public switched network (PSN) for the Government Emergency Telecommunications Service (GETS).

A standard format for placing fields and directories on CD ROM, revised and adopted by the International Organization for Standardization as ISO
966
0. [After Silicon]

An electromagnetic pulse produced at an altitude effectively above the sensible atmosphere, i.e., above about 120 km.

Television that has approximately twice the horizontal and twice the vertical emitted resolution specified by the NTSC standard.
Note 1: In HDTV, the total number of pixels is therefore approximately four times that of the NTSC standard.
Note 2: HDTV may include any or all improved-definition television (IDTV) and extended-television (EDTV) improvements.
Note 3: HDTV employs a wide aspect ratio.

A distribution frame that provides terminating and interconnecting facilities for those combined supergroup modulator output circuits and combined supergroup demodulator input circuits that contain signals occupying the baseband spectrum.

In the hierarchical structure of a primary or secondary data transmission station, the conceptual level of control or processing logic that (a) is above the Link Level and (b) controls Link Level functions, such as device control, buffer allocation, and station management.