ADTRAN Atlas 800 Plus, User Manual

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Appendix E. Glossary
61200226L1-1 ATLAS 800
PLUS
User Manual E-5
option modules
Any optional, hot-swappable module that can be added to the ATLAS 800 system for a variety of
applications. See also
overbooking
ATLAS 800 feature that reduces telecommunications expenses by allowing you to over-subscribe
switched bandwidth for situations where simultaneous access to the network by every subscriber is
not required.
PBX
private branch exchange. A telephone system usually owned by the customer that serves a particular
location. It provides connections from one phone extension to another and connects to the external
telephone network.
PRI
Primary Rate ISDN. An ISDN service that provides 23 B (bearer) channels (64 kbps each) and 1 D
(data) channel (64 kpbs). The combined capacities are equivalent to one T1 channel.
Quad Nx56/64 Module
(Nx is pronounced "en-by.") One of the ATLAS 800 option modules. The Quad Nx56/64 Module pro-
vides four synchronous V.35 DTE ports, each of which can operate at any rate that is a multiple of 56 or
64 kbps, up to 1.536 Mbps.
Quad T1/PRI Module
One of the ATLAS 800 option modules. The Quad T1/PRI Module provides four channelized T1 or
Primary Rate ISDN (PRI) interfaces. Each interface can operate independently in DS-1 or DSX-1 mode,
and any port can serve as the primary or backup timing source for the entire system.
Remote Access
The ability to connect to non-local communications equipment.
robbed bit signaling
A type of in-band signaling used with voice transmissions for multiplexing multiple voice circuits
onto a T1.
SNMP
Simple Network Management Protocol. A control and reporting scheme widely used to manage
devices from different vendors. SNMP operates on top of the Internet protocol.
synchronous
1.The condition occurring when two events happen in a specific time relationship with each other,
both under control of a master clock.
2 A method of data transmission requiring the transmission of timing pulses to keep the sender and
receiver synchronized in their communication used to send blocks of information. Synchronous data
transmission is used in high speed data circuits because there is less overhead than asynchronous
transmission of characters which contain two extra bits per character to affect timing.
T1 circuit
Also T-1. A digital transmission link with a capacity of 1.544 Mbps. T1 uses two pairs of normal
twisted wires. T1 normally can handle 24 voice conversations with each conversation being digitized
at 64 kbps. With more advanced digital voice encoding techniques, it can handle more voice channels.
T1 is a standard for digital transmission in North America.