IBM AnyPlace Kiosk 4838 Model 5 Series, Руководство по обслуживанию

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cluster. (1) A station that consists of a control unit (a
cluster controller) and the terminals attached to it. (2) A
group of APPN nodes that have the same network ID
and the same topology database. A cluster is a subset
of a NETID subnetwork. (3) In high-availability cluster
multiprocessing (HACMP
™
), a set of independent
systems (called nodes) that are organized into a
network for the purpose of sharing resources and
communicating with each other.
collision. (1) An unwanted condition that results from
concurrent transmissions on a channel. (T) (2) When a
frame from a transmitting adapter encounters any other
signal in its path (frame, noise, or another type of
signal), the adapter stops transmitting and a collision is
registered.
command. (1) A request for performance of an
operation or execution of a program. (2) A character
string from a source external to a system that
represents a request for system action.
component. (1) Any part of a network other than an
attaching device, such as an IBM 8228 Multistation
Access Unit. (2) Hardware or software that is part of a
functional unit.
configuration.
(1) The devices and programs that
make up a system, subsystem, or network. (A) See also
system configuration . (2) In the IBM StorePlace
Distributed Data Services for OS/2, program options
that are initially set at installation, and that can be
changed later. Changing these options requires an IPL.
These changes must be performed by a programmer or
store operations personnel. These options are used to
tune the product's use of the operating system and
system resources.
connect. In a LAN, to physically join a cable from a
station to an access unit or network connection point.
Contrast with
attach .
controller. A unit that controls input/output
operations for one or more devices.
cursor. A movable point of light (or a short line) that
indicates where the next character is to be entered on
the display screen.
D
data. (1) A representation of facts, concepts, or
instructions in a formalized manner suitable for
communication, interpretation, or processing by human
or automatic means. (I) (A) (2) Any representations
such as characters or analog quantities to which
meaning is or might be assigned. (A)
data file. A collection of related data records
organized in a specific manner; for example, a payroll
file (one record for each employee, showing such
information as rate of pay and deductions) or an
inventory file (one record for each inventory item,
showing such information as cost, selling price, and
number in stock.) See also
data set, file .
data processing system. A system, including computer
systems and associated personnel, that performs input,
processing, storage, output, and control functions to
accomplish a sequence of operations on data. (A) (I)
data set. Logically related records treated as a single
unit. See also file .
DBCS.
See double-byte character set .
device. (1) A mechanical, electrical, or electronic
contrivance with a specific purpose. (2) An
input/output unit such as a terminal, display, or
printer. See also
attaching device .
diagnostic diskette. A diskette containing diagnostic
modules or tests used by computer users and service
personnel to diagnose hardware problems.
diagnostics. Modules or tests used by computer users
and service personnel to diagnose hardware problems.
digital. (1) Pertaining to data in the form of digits. (A)
Contrast with analog . (2) Pertaining to data consisting
of numerical values or discrete units.
DIP switch. A two-position switch on a circuit board
that is preset to control certain functions. The user can
change the position of a DIP switch to satisfy special
requirements.
disk. A round, flat, data medium that is rotated in
order to read or write data. (T) See also diskette,
hard-disk drive .
disk operating system (DOS). A computer operating
system that can perform only one task at a time.
diskette.
A thin, flexible magnetic disk permanently
enclosed in a protective jacket. A diskette is used to
store information for processing.
diskette drive. The mechanism used to seek, read, and
write data on diskettes.
display. (1) A visual presentation of data. (2) A device
that presents visual information to the point-of-sale
terminal operator and to the customer.
distributed. Physically separate but connected by
cables.
DOS. See disk operating system .
double-byte character set (DBCS). A set of characters
in which each character is represented by 2 bytes.
Languages such as Japanese, Chinese, and Korean,
which contain more symbols than can be represented
by 256 code points, require double-byte character sets.
Because each character requires 2 bytes, the typing,
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IBM AnyPlace Kiosk 4838