IBM Nways 2216, Руководство по обслуживанию и ремонту

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one or more other link stations; for example, a
telecommunication line and data circuit-terminating
equipment (DCE). Synonymous with
data circuit.
LMI. Local management interface.
local. Pertaining to a device accessed directly without
use of a telecommunication line.
local area network (LAN). (1) A computer network
located on a user's premises within a limited
geographical area. Communication within a local area
network is not subject to external regulations; however,
communication across the LAN boundary may be
subject to some form of regulation. (T) (2) A network in
which a set of devices are connected to one another for
communication and that can be connected to a larger
network. See also
Ethernet and token ring.
(3) Contrast with metropolitan area network (MAN) and
wide area network (WAN).
logical partition (LP). A subset of the processor
hardware that is defined to support the operation of a
system control program (SCP). See also
logically
partitioned (LPAR) mode.
logically partitioned (LPAR) mode. A central
processor complex (CPC) power-on reset mode that
enables use of the PR/SM feature and allows an
operator to allocate CPC hardware resources (including
central processors, central storage, expanded storage,
and channel paths) among logical partitions. In LPAR
mode, the ESCON adapter can share a physical fiber
connection with multiple host partitions.
LP. Logical partition.
LP number. Logical partition number. This allows
multiple logical host partitions, LPs to share one
ESCON fiber. This value is defined in the host
Input/Output Configuration Program (IOCP) by the
RESOURCE macro instruction. If the host is not using
EMIF, use the default of 0 for the LP number.
LPAR. Logically partitioned.
LPAR mode. Logically partitioned mode.
LS. Low-speed.
LSA. Low-speed adapter (module).
M
MAN. Metropolitan area network.
Management Information Base (MIB). (1) A
collection of objects that can be accessed by means of
a network management protocol. (2) A definition for
management information that specifies the information
available from a host or gateway and the operations
allowed. (3) In OSI, the conceptual repository of
management information within an open system.
MB. Megabyte (1 000 000 bytes).
Mbps. Megabits per second (1 000 000 bits per
second).
metropolitan area network (MAN). A network formed
by the interconnection of two or more networks which
may operate at higher speed than those networks, may
cross administrative boundaries, and may use multiple
access methods. (T) Contrast with
local area network
(LAN) and wide area network (WAN).
MIB. (1) MIB module. (2) Management Information
Base.
modem (modulator/demodulator). (1) A functional
unit that modulates and demodulates signals. One of
the functions of a modem is to enable digital data to be
transmitted over analog transmission facilities. (T) (A)
(2) A device that converts digital data from a computer
to an analog signal that can be transmitted on a
telecommunication line, and converts the analog signal
received to data for the computer.
MPC. Multi-Path Channel.
MPC+. High-Performance Data Transfer (HPDT)
Multi-Path Channel.
ms. Millisecond (1/1000 second).
N
network. (1) A configuration of data processing
devices and software connected for information
interchange. (2) A group of nodes and the links
interconnecting them.
network architecture. The logical structure and
operating principles of a computer network. (T)
Note: The operating principles of a network include
those of services, functions, and protocols.
network management. The process of planning,
organizing, and controlling a communication-oriented
data processing or information system.
NIC. Network Information Center.
NMS. Network management station.
NNI. Network-to-network interface.
non-return-to-zero change-on-ones recording
(NRZ-1). A recording method in which the ones are
represented by a change in the condition of
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2216 Maintenance Manual