IBM SAN32M1, Installation And Service Manual

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SAN32M1 Fabric Switch Installation and Service Manual 538
dB
See decibel .
dBm Decibels referenced to one milliwatt. Zero dBm equals one milliwatt,
with a logarithmic relationship as the value increases (D).
DC See direct current .
decibel Abbreviated as dB. A standard unit used to express gain or loss of
optical power, expressed as the ratio of input power to output power
on a logarithmic basis (D).
default Pertaining to an attribute, value, or option that is assumed by a sys-
tem when none is explicitly specified (D, I).
default zone A zone that contains all attached devices that are not members of a
separate active zone.
destination A point or location, such as a processor, director or switch, or server,
to which data is transmitted (D).
device
(1) Mechanical, electrical, or electronic hardware with a specific pur-
pose (D). See also
managed product .
(2) See node .
diagnostics (1) The process of investigating the cause or nature of a problem in a
product or system. (2) Procedures or tests used by computer users
and service personnel to diagnose hardware or software problems
(D).
dialog box A pop-up window in the user interface with informational messages
or fields to be modified or completed with desired options.
direct current
DC. Electric current that continuously flows in one direction (D). Con-
trast with
alternating current .
director An intelligent, highly-available, Fibre Channel switch providing
any-to-any port connectivity between nodes (end devices) on a
switched fabric. The director sends data transmissions (data frames)
between nodes in accordance with the address information present in
the frame headers of those transmissions.
diskette A thin magnetic disk enclosed in a plastic jacket, which is removable
from a computer and is used to store and transport data (D).