IBM 8285 Nways, Installation And User Manual

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trunk. A physical topology, either open or closed,
employing two optical fiber signal paths, one in each
direction (that is, counter-rotating), forming a sequence
of peer connections between FDDI nodes. When the
trunk forms a closed loop it is sometimes called a trunk
ring.
TRS. Topology Routing Service.
twisted pair. A transmission medium that consists of
two insulated conductors twisted together to reduce
noise. (T)
TX. Transmit.
U
UNI. User-network interface.
UNIX operating system. An operating system
developed by Bell Laboratories that features
multiprogramming in a multiuser environment. The UNIX
operating system was originally developed for use on
minicomputers, but has been adapted for mainframes
and microcomputers.
Note: The AIX operating system is IBM’s
implementation of the UNIX operating system.
user-network interface (UNI). Physical and logical
definition of the interface between an ATM user device
and the ATM network.
UTP. Unshielded twisted pair.
V
V. Volt.
V ac. Volts alternating current.
variable. (1) In computer programming, a character or
group of characters that refers to a value and, in the
execution of a computer program, corresponds to an
address. (2) A quantity that can assume any of a given
set of values. (A)
VBR. Variable bit rate.
VCC. Virtual channel connection.
VCI. Virtual channel identifier (in ATM cell header).
VPI. Virtual path identifier (in ATM cell header).
W
WAN. Wide area network.
wide area network (WAN). (1) A network that provides
communication services to a geographic area larger than
that served by a local area network or a metropolitan
area network, and that may use or provide public
communication facilities. (T) (2) A data communications
network designed to serve an area of hundreds or
thousands of miles; for example, public and private
packet-switching networks and national telephone
networks. (3) Contrast with
local area network (LAN)
and metropolitan area network (MAN).
wiring closet. A room that contains one or more
distribution panels and equipment racks that are used to
interconnect cables. Sometimes called a
network wiring
closet to distinguish it from a telephone wiring closet.
workstation. (1) A functional unit at which a user
works. A workstation often has some processing
capability. (T)
(2) One or more programmable or
nonprogrammable devices that allow a user to do work.
(3) A terminal or microcomputer, usually one that is
connected to a mainframe or to a network, at which a
user can perform applications.
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IBM 8285 Nways ATM Workgroup Switch: Installation and User’s Guide