IBM Netfinity 3000, User Handbook Manual

Page: 334 / 370

contention by using carrier sense
and deference, and resolves
contention by using collision
detection and transmission.
Ethernet uses carrier sense multiple
access with collision detection
(CSMA/CD).
F
FDX . Full-duplex. Synonymous
with duplex. Contrast with HDX.
file . A named set of records stored
or processed as a unit. (T)
flash memory
. See electrically
erasable programmable read-only
memory (EEPROM).
frame . (1) A data structure that
consists of fields, predetermined by
a protocol, for the transmission of
user data and control data. The
composition of a frame, especially
the number and types of fields, may
vary according to the type of
protocol. (T)
frequency . The rate of signal
oscillation, expressed in hertz.
G
group address (GADDR) . (1) In
communications, a multidestination
address associated with one or more
stations on a network. Contrast
with individual address. (2) In
Synchronous Data Link Control
(SDLC), an address in addition to a
specific address that is common to
two or more secondary stations.
H
half-duplex . In data
communication, pertaining to
transmission in only one direction at
a time. Contrast with duplex.
hard disk . A rigid magnetic disk
such as the internal disks used in
the system units of
personal-computer systems and in
external hard disk drives.
hard disk drive
. A disk drive that
reads and writes data on rigid disks
and can be installed in or connected
to a computer.
hardware
. (1) All or part of the
physical components of an
information processing system, such
as computers or peripheral devices.
(T) (2) The equipment, as opposed
to the programming, of a computer.
(3) Contrast with software.
HDX . Half-duplex.
hexadecimal . Pertaining to a
system of numbers to the base 16;
hexadecimal digits range from 0
through 9 and A through F, where
A represents 10 and F represents 15.
hot swap . (1) A hard disk
subsystem feature of servers and
storage enclosures that enables you
to remove and replace hard disk
drives without turning off the
system. (2) To replace a hard disk
drive while the system is turned on.
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Netfinity 3000 User's Handbook