Carrier Access Access Navigator, Руководство пользователя

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GlossaryGlossaryGlossaryGlossary-10 August 2003 Access Navigator - Release 1.8
Glossary
Line Loopback
A connection that loops back the entire signal along with the original framing.
Line Overhead
The traffic management portion of a communications system that is transported in
the overhead bits of communications links such as DS1, DS3, and SONET.
Line Terminat-
ing Equipment
LTE. Network elements such as add/drop multiplexers or digital crossconnect
systems which can access, generate, and process Line Overhead.
Local Area
Network
LAN. Usually refers to a network connecting users in physical proximity, such a
one floor or one building.
Loopback
A temporary test connection in a communications network that loops the transmit
signal line back towards the receive signal line in order to verify the signal path.
Management
Information
Base
MIB. A database used by Simple Network Management Protocol (SNMP)
systems to check network statistics and configurations.
Multiplex
MUX. To transmit two or more signals over a single channel.
Multiplexer
MUX. A device for combining several channels to be carried by one line or fiber.
Narrowband
Services requiring up to 1.5 Mbps transport capacity.
Network
Element
NE. Any device that is part of a communications network and can terminate
section, line, or path overhead functions.
Orderwire
A channel used by installers to expedite the provisioning of lines.
Overhead
Extra bits in a digital stream used to carry information besides traffic signals.
Orderwire, for example, would be considered overhead information.
P-Phone
Proprietary Phone, also called an Electronic Business Set (EBS), is an analog
Centrex service offered by Nortel and supported by Nortel DMS switches and
P-Phone compatible telephone stations. The analog signal between the P-Phone
and Central Office is a single-pair subscriber loop providing normal full-duplex
analog voice and an 8-kHz half-duplex amplitude-shift-keyed signal that carries
signaling information. Nortel NIS V202-1 specifies the GR-303 requirements for
a remote digital terminal (RDT) interface with the Nortel DMS switch.
Parity
An error-checking scheme which examines the number of transmitted bits in a
block which hold the value one. For even parity, an overhead parity bit is set to
either one or zero to make the total number of transmitted ONES an even number.
For odd parity, the parity bit is set to make the total number of ONES transmitted
an odd number.
Path
A logical connection between two points in a network, which may follow many
physical paths.