IBM Netfinity 3000, Руководство пользователя

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wired so that each signal wire is
terminated at the same pin position
at each end of the cable. A
straight-through cable is used to
connect the 10BASE-T port on an
Ethernet controller to a 10BASE-T
port on a repeater that performs the
crossover function.
subsystem . In computers, a
secondary or subordinate system,
usually capable of operating
independently of a controlling
system, and usually having a single
purpose, such as displaying video
or reading from and writing to hard
disks. A subsystem can be
integrated into the system board or
on an adapter.
SVGA . Super video graphics array.
symmetric multiprocessing . In
personal-computer systems, a
multiprocessing design that enables
two or more microprocessors to run
concurrently and work
independently, with each
microprocessor capable of
performing any task.
synchronous transmission .
(1) Data transmission in which the
time of occurrence of each signal
representing a bit is related to a
fixed time base. (I) (2) In data
communication, a method of
transmission in which the sending
and receiving of characters are
controlled by timing signals.
Contrast with asynchronous
transmission.
Note: The sending and receiving
devices are operated at substantially
the same frequency and are kept in
an appropriate phase relationship.
system board . In a system unit, the
main circuit board that supports a
variety of basic system devices, such
as a keyboard or a mouse, and
provides other basic system
functions.
system unit . In personal-computer
systems, the part of the computer
that contains the processor circuitry,
read-only memory (ROM), random
access memory (RAM), and the I/O
channel.
T
telephone twisted pair . One or
more twisted pairs of copper wire in
the unshielded voice-grade cable
commonly used to connect a
telephone to its wall jack. Also
referred to as unshielded twisted
pair (UTP).
transceiver . A physical device that
connects a host interface to a local
area network, such as Ethernet.
Ethernet transceivers contain
electronics that apply signals to the
cable and sense collisions.
Transmission Control Protocol
(TCP)
. A communications protocol
used in Internet and in any network
that follows the U.S. Department of
Defense standards for inter-network
protocol. TCP provides a reliable
host-to-host protocol between hosts
in packet-switched communications
networks and in interconnected
systems of such networks. It
Glossary
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