IBM TotalStorage DS4000 Hardware Maintenance Manual page 177

switch zoning. See zoning.
synchronous write mode. In remote mirroring, an
option that requires the primary controller to wait for
the acknowledgment of a write operation from the
secondary controller before returning a write I/O
request completion to the host. See also asynchronous
write mode, remote mirroring, Metro Mirroring.
system name. Device name assigned by the vendor's
third-party software.
TCP. See Transmission Control Protocol.
TCP/IP. See Transmission Control Protocol/Internet
Protocol.
terminate and stay resident program (TSR program).
A program that installs part of itself as an extension of
DOS when it is executed.
topology. The physical or logical arrangement of
devices on a network. The three fibre-channel
topologies are fabric, arbitrated loop, and
point-to-point. The default topology for the disk array
is arbitrated loop.
TL_port. See translated loop port.
transceiver. A device that is used to transmit and
receive data. Transceiver is an abbreviation of
transmitter-receiver.
translated loop port (TL_port). A port that connects to
a private loop and allows connectivity between the
private loop devices and off loop devices (devices not
connected to that particular TL_port).
Transmission Control Protocol (TCP). A
communication protocol used in the Internet and in
any network that follows the Internet Engineering Task
Force (IETF) standards for internetwork protocol. TCP
provides a reliable host-to-host protocol between hosts
in packed-switched communication networks and in
interconnected systems of such networks. It uses the
Internet Protocol (IP) as the underlying protocol.
Transmission Control Protocol/Internet Protocol
(TCP/IP). A set of communication protocols that
provide peer-to-peer connectivity functions for both
local and wide-area networks.
trap. In the Simple Network Management Protocol
(SNMP), a message sent by a managed node (agent
function) to a management station to report an
exception condition.
trap recipient. Receiver of a forwarded Simple
Network Management Protocol (SNMP) trap.
Specifically, a trap receiver is defined by an Internet
Protocol (IP) address and port to which traps are sent.
Presumably, the actual recipient is a software
application running at the IP address and listening to
the port.
TSR program. See terminate and stay resident program.
uninterruptible power supply. A source of power
from a battery that is installed between a computer
system and its power source. The uninterruptible
power supply keeps the system running if a
commercial power failure occurs, until an orderly
shutdown of the system can be performed.
user action events. Actions that the user takes, such as
changes in the storage area network (SAN), changed
settings, and so on.
worldwide name (WWN). A unique identifier for a
switch on local and global networks.
WORM. See write-once read-many.
write-once read many (WORM). Any type of storage
medium to which data can be written only a single
time, but can be read from any number of times. After
the data is recorded, it cannot be altered.
WWN. See worldwide name.
zoning. (1) In Fibre Channel environments, the
grouping of multiple ports to form a virtual, private,
storage network. Ports that are members of a zone can
communicate with each other, but are isolated from
ports in other zones. (2) A function that allows
segmentation of nodes by address, name, or physical
port and is provided by fabric switches or hubs.
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Glossary