IBM 300 Service Manual page 151

line. In a 2220 network, any physical medium, such as
a telephone wire, microwave beam, or optical fiber, that
transmits information. A line can be a trunk line or a port
line.
line connection box (LCB). A metallic box that:
v Multiplexes up to 15 low-speed lines. There can be
up to four LCBs per LIC type 511 for a total of 60
lines (two LCBs and 30 lines per LIC connector).
v Reduces cable lengths between Nways Switch and
DCE or DTE locations.
An LCB fits in a standard 19-inch rack. Each one
houses up to 15 active remote connectors (ARCs).
line interface coupler (LIC). In an Nways Switch, a
module that physically attaches trunk or port lines. Each
line interface coupler is associated with a trunk or port
adapter, and supports specific line interfaces.
LIV. Link integrity verification.
LMI. Local management interface.
local area network (LAN). A computer network
located on a user premises in a limited geographical
area.
logical port. (Also called NBBS port.) A logical
resource generated by the Nways Switch Control
Program to provide access services to a physical port
line (or channel of a TDM port line) using HDLC, FR, or
CES protocol. A logical port sets up and maintains its
predefined connections.
logical trunk. (Also called NBBS trunk.) A logical
resource generated by the Nways Switch Control
Program to provide transport services to a physical
trunk line (or channel of a TDM trunk line). A logical
trunk is mainly responsible for optimizing bandwidth and
maintaining the CP spanning tree.
LSAn. Low-speed adapter type n (module).
MA/SR. Multi-access/sub-rate.
management access. Refers to an Nways Switch that
connects a network management station or a change
control server to a 2220 network through its service bus,
which is a dedicated Ethernet LAN.
MB. Megabyte (storage capacity, 1 048 576 bytes).
Mbps. Megabit per second (10 to the power of 6 bits
per second).
MBS. Maximum burst size.
MLT. Multiple logical trunks.
module. In an Nways Switch, a hardware unit plugged
in a slot of the logic subrack. It houses, for example, an
adapter, a line interface coupler, or a voice server
extension. All modules are hot pluggable.
ms. Millisecond (1/1000 second).
NAS. Nways Switch administration station.
NBBS. Networking BroadBand Services (architecture).
NBBS architecture. See Networking BroadBand
Services.
NBBS connection. See potential connection and
virtual connection.
NBBS network. A network built with IBM 2220 Nways
BroadBand Switches and conforming to the IBM
Networking BroadBand Services (NBBS) architecture.
NBBS port. See logical port.
NBBS trunk. See logical trunk.
NCT2. Nways Switch Configuration Tool Version 2.
NDPS. Non-disruptive path switching.
NEM. Nways Enterprise Manager (see 2220 Nways
Switch Manager).
network control. Functions that are performed by an
Nways Switch control point to:
v Allocate and control the Nways Switch resources
v Provide topology and directory services
v Select routes
v Control congestion.
network management station (NMS). A station that
runs IBM NetView for AIX and the 2220 Nways Switch
Manager. It is used to manage network topology,
accounting, performance, configuration, and error
reporting.
network node interface (NNI). An interface between
nodes in a communication network.
Network Support Center (NSC). A location from
which IBM remotely supports 2220 networks.
Networking BroadBand Services (NBBS). An IBM
architecture for high-speed networking that
complements ATM standards and provides access
services, transport services, and network control to user
traffic.
NIC. Network Information Center.
NMS. Network management station.
NNI. Network node interface.
NPT. Numbering plan table.
NR. Non-reserved.
E-5
Glossary