IBM 8237, Инструкция по установке и эксплуатации

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Glossary of Terms and Abbreviations
X-7
or communications and systems management (C&SM)
services.
network. (1) A configuration of data processing
devices and software connected for information
interchange. (2) An arrangement of nodes and
connecting branches. Connections are made between
data stations. (T)
network layer. (1) In the Open Systems
Interconnection reference model, the layer that
provides for the entities in the transport layer the
means for routing and switching blocks of data through
the network between the open systems in which those
entities reside. (T) (2) The layer that provides services
to establish a path between systems with a predictable
quality of service. See
Open Systems Interconnection
(OSI).
network management. The conceptual control
element of a station that interfaces with all of the
architectural layers of that station and is responsible for
the resetting and setting of control parameters,
obtaining reports of error conditions, and determining if
the station should be connected to or disconnected
from the network.
network manager. A program or group of programs
that is used to monitor, manage, and diagnose the
problems of a network.
node. (1) Any device, attached to a network, that
transmits and/or receives data. (2) An endpoint of a
link, or a junction common to two or more links in a
network. (3) In a network, a point where one or more
functional units interconnect transmission lines.
nonvolatile random access memory (NVRAM).
Random access memory that retains its contents after
electrical power is shut off.
null-modem cable. An EIA 232 serial cable wired so
two terminals can communicate without the use of
modems.
NVRAM. Nonvolatile random access memory.
O
octet. A byte that consists of 8 bits. (T)
ohm. A unit of measure of electrical resistance.
Open Systems Interconnection (OSI). (1) The
interconnection of open systems in accordance with
specific ISO standards. (T) (2) The use of standardized
procedures to enable the interconnection of data
processing systems.
Note: OSI architecture establishes a framework for
coordinating the development of current and future
standards for the interconnection of computer systems.
Network functions are divided into seven layers. Each
layer represents a group of related data processing and
communication functions that can be carried out in a
standard way to support different applications.
Open Systems Interconnection (OSI) architecture.
Network architecture that adheres to a particular set of
ISO standards that relates to Open Systems
Interconnection. (T)
Open Systems Interconnection (OSI) reference
model. A model that represents the hierarchical
arrangement of the seven layers described by the
Open Systems Interconnection architecture.
operation. (1) A defined action, namely, the act of
obtaining a result from one or more operands in
accordance with a rule that completely specifies the
result for any permissible combination of operands. (A)
(2) A program step undertaken or executed by a
computer. (3) An action performed on one or more
data items, such as adding, multiplying, comparing, or
moving.
option. (1) A specification in a statement, a selection
from a menu, or a setting of a switch, that may be used
to influence the execution of a program. (2) A
hardware or software function that may be selected or
enabled as part of a configuration process. (3) A piece
of hardware (such as a network adapter) that can be
installed in a device to modify or enhance device
function.
out-of-band. A communication data stream
transmitted outside the primary signaling channel or
frequency band.
output device. A device in a data processing system
by which data can be received from the system. (I) (A)
Synonymous with
output unit.
output unit. Synonym for
output device.
P
parallel port. A port that transmits the bits of a byte in
parallel along the lines of the bus, 1 byte at a time, to
an I/O device. On a personal computer, it is used to
connect a device that uses a parallel interface, such as
a dot matrix printer, to the computer. Contrast with
serial port.
path. (1) In a network, any route between any two
nodes. (T) (2) The route traversed by the information
exchanged between two attaching devices in a
network. (3) A command in IBM Personal Computer
Disk Operating System (PC DOS) and IBM Operating
System/2 (OS/2) that specifies directories to be
searched for commands or batch files that are not
found by a search of the current directory.
personal computer (PC). A desk-top, free-standing,
or portable microcomputer that usually consists of a
system unit, a display, a monitor, a keyboard, one or