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Network channel-terminating equipment, Nonfacility-associated signaling – AT&T DEFINITY 7200 series User Manual

Page 329

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GLOSSARY

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MPDM

See modular processor data module.

MTDM

See modular trunk data module.

mu-255

A type of code by which analog signals are encoded to digital signals.

multiplexer

A device used to combine a number of individual channels into a common
bit stream for transmission.

multiplexing

A process whereby a transmission facility is divided into two or more
channels, either by splitting the frequency band into a number of narrower
bands or by dividing the transmission channel into successive time slots.
See also time-division multiplexing.

nailed-up connection

Obsolete. See dedicated switched connection and permanent switched
connection
.

NCTE

See network channel-terminating equipment.

network

A series of points, nodes, or stations connected by communications
channels.

network-access unit
(NAU)

A circuit card that plugs into a PC’s expansion slot to connect that PC with
others to form a StarLAN network. See also StarLAN.

network channel-
terminating equipment
(NCTE)

Equipment used at a customer’s premises to provide facility terminations
and signaling compatibility. Also called channel service unit and
customer service unit. See also data service unit.

node

A switching or control point for a network. Nodes are either tandem
they receive signals and pass them on — or terminal — they originate or
terminate a transmission path.

nonfacility-associated
signaling (NFAS)

A method that allows multiple PRI links to share a single D-channel on
one of the spans. One T1 link is therefore configured as 23 B-channels
plus 1 D-channel, while the other spans that share the D-channel are
configured with 24 B-channels each. See also facility-associated
signaling
and primary rate interface.

off premises

Telephones or data terminals that are not located within the same building
or campus as a communications system or have loop lengths greater than
3500 feet.

off-hook

A condition in which the handset of a telephone is off the switchhook or
the telephone is activated by other means, such as through a speakerphone
button.