IBM xSeries 300, Service Manual

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NRT. Non-real-time.
NRZI. Non-return-to-zero inverted recording.
NRZ-1. Non-return-to-zero change-on-ones recording.
NSAP. Network service address point.
NSC. Network Support Center.
NSM. (See 2220 Nways Switch Manager)
NVDM. NetView Distribution Manager for AIX.
NTT. Nippon Telegraph & Telephone (Corporation).
numbering plan table (NPT). A set of parameters,
organized in origin NPT and destination NPT, that
defines a type of called ISDN numbers. A numbering
plan table is associated with each ISDN network
interface.
Nways 2220 Switch Manager (2220 Switch
Manager). An IBM licensed program that runs under
NetView for AIX to manage the 2220 Nways Switch
operation and configuration from a network
management station. It replaces the Nways Enterprise
Manager (NEM) which is no longer available.
Nways BroadBand Switch. Synonym for 2220 Nways
BroadBand Switch.
Nways Enterprise Manager (NEM). An IBM licensed
program that was used under NetView for AIX in a
network management station to manage Nways
Switches, routers, and bridges in a 2220 network (see
2220 Nways Switch Manager).
Nways Switch. Synonym for 2220 Nways BroadBand
Switch.
Nways Switch administration station (NAS). A
station attached to each 2220 to run the Control
Program, and control and service the Nways Switch
locally.
Nways Switch configuration station. A mandatory
OS/2 or AIX station that runs a stand-alone version of
the Nways Switch Configuration Tool Version 2 (NCT2)
and stores the centralized configuration database of the
NBBS network. An OS/2 station can be used as a
remote user console.
Nways Switch Configuration Tool Version 2 (NCT2).
A component of the Nways Switch Control Program that
is used to configure physical and logical resources. It is
also used in stand-alone version under OS/2 or AIX .
Nways Switch Control Program. The IBM licensed
program that runs in the NAS and adapters of the 2220
Nways Switch. It includes a CMIP agent to work with
the 2220 Switch Manager.
Nways 2220 Switch Manager for AIX. (See Nways
2220 Switch Manager)
Nways Switch Resource Control. A component of
the Nways Switch Control Program. It is used from the
NAS of an Nways Switch or from a remote user console
to control resources and configuration files.
OAM. Operation, administration, and maintenance.
OC3. Optical carrier level 3.
ONPT. Origin numbering plan table.
operation, administration, and maintenance (OAM).
A group of functions coded in specific ATM cells to
handle alarms and loopback tests on ATM connections.
optical fiber. In fiber optics technology, a wave guide
that propagates optical signals from light-generating
transmitters to light-detecting receivers.
OSI. Open systems interconnection.
packet loss ratio. The probability that a packet will
not reach its destination or not reach it in a specified
time. It is obtained by dividing the number of packets
lost in transmission by the total number transmitted.
packet transfer mode (PTM). The native transfer
mode of the NBBS architecture. PTM divides the traffic
into packets of variable length.
PBX. Private branch exchange.
PCM. Pulse code modulation.
PCR. Peak cell rate.
PDH. Plesiochronous digital hierarchy.
permanent virtual circuit (PVC). A virtual circuit that
has a logical channel permanently assigned to it at each
item of data terminal equipment. It is activated by a
program or by a network operator request.
plesiochronous. Refers to transmission at a nominal
bit rate where the source and destination are controlled
by different clocks. The bit rates are nearly the same.
PLP. Packet layer protocol.
PNP. Private numbering plan.
port. See logical port.
port adapter. In an Nways Switch, a module that
provides access services to one or more port lines.
Each port adapter is associated with a line interface
coupler (LIC).
port line. A communication line that connects a device
on user premises to an Nways Switch and serves as a
port to the 2220 network. Port lines have different
protocols and interfaces.
E-6
2220 Setup and Service Guide