Network Device, DL3800E User's Guide

G-10 DL3800E Inverse Multiplexer User’s Guide — July 9, 2001
G
multidrop
A communications arrangement where multiple devices share a common
transmission channel, though only one may transmit at a time.
N
NEBS
A network Equipment Building Systems requirement. A standard issued by
Bellcore that spells out central office standards for grounding, cabling and
power.
network
An interconnection of computer systems, terminals, or data communications
facilities.
NI (Network Interface)
The point of demarcation between the customer premises and the carrier's
network, usually drawn at the network connector on the rear panel of the
Quick Eagle Networks access device.
NRZ (Non-Return to Zero)
A binary encoding and transmission scheme where “ones” and “zeros” are
represented by opposite, and alternating, high and low voltages.
NRZI (Non-Return to Zero Inverted)
A binary encoding technique that inverts the signal on a “one” and leaves the
signal unchanged for a “zero,” where a change in voltage state signals a “one”
bit and the absence of a change denotes a “zero” bit value.
O
OOS (Out of Service)
A digital network trouble signal.
OOF (Out of Frame)
An error checking scheme. An OOF occurs when two out of four consecutive
framing bits are in error.
P
parity bit
An additional, non-informational bit appended to a group of bits indicating
that the number of “ones” in the bits group is odd or even.
parity check
A process of error checking using the parity bit.