IBM SAN16B-2 - TotalStorage Express Model Switch, User And Service Manual

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node port (N_port). A port on a node that can
connect to a Fibre Channel port or to another N_Port in
a point-to-point connection.
nonparticipating mode. A mode in which a loop port
(L_port) in a loop is inactive and cannot arbitrate or
send frames, but can retransmit any received
transmissions. This mode is entered if there are more
than 127 devices in a loop and an arbitrated loop
physical address (AL_PA) cannot be acquired. See also
participating mode .
nonvolatile random access memory (NVRAM).
Random access memory (storage) that retains its
contents after the electrical power to the machine is
shut off. A specific part of NVRAM is set aside for use
by the system ROS for the boot device list.
N_port. See node port .
NTP. See network time protocol
NVRAM. See nonvolatile random access memory .
Nx_port. A node port that can operate as either a
node port (N_port) or node loop port (NL_port). See
also node port and node loop port .
O
operating system (OS). A collection of system
programs that control the overall operation of a
computer system.
ordered set. A transmission word that uses 8b/10b
mapping and begins with the K28.5 character. Ordered
sets occur outside of frames, and include frame
delimiters, primitive signals, and primitive sequences.
Ordered sets are used to differentiate Fibre Channel
control information from data frames and to manage the
transport of frames. See also frame delimiter , primitive
signal , and primitive sequence.
OS. See operating system .
out-of-band. Transmission of management protocol
outside of the Fibre Channel network, usually over
Ethernet.
P
packet. A set of information transmitted across a
network. See also frame .
parallel. The simultaneous transmission of data bits
over multiple lines.
participating mode. A mode in which a loop port
(L_port) in a loop has a valid arbitrated loop physical
address (AL_PA) and can arbitrate, send frames, and
retransmit received transmissions. See also
nonparticipating mode .
path selection. The selection of a transmission path
through the fabric. Switches use the Fibre Channel
shortest path first (FSPF) protocol.
PDU. Power distribution unit.
Performance Monitoring. A software feature that
provides error and performance information to the
administrator and user for use in storage management.
phantom address. An arbitrated loop physical
address (AL_PA) value that is assigned to a device that
is not physically in the loop. Also known as phantom
AL_PA.
phantom device. A device that is not physically in an
arbitrated loop, but is logically included through the use
of a phantom address.
PLDA. See private loop direct attach .
PLOGI. See port login .
P/N. Part number.
point-to-point. A Fibre Channel topology that employs
direct links between each pair of communicating
entities. See also topology .
port cage. The metal casing extending out of the
optical port on the switch, and in which the gigabit
interface converter (GBIC) or small form-factor
pluggable (SFP) can be inserted.
port card. A hardware component that provides a
platform for field-replaceable, hot swappable ports.
port login (PLOGI). The port-to-port login process by
which initiators establish sessions with targets. See also
fabric login .
port module. A collection of ports in a switch.
port_name. The unique identifier assigned to a Fibre
Channel port. Communicated during login and port
discovery.
POST. See power-on self-test .
PPP. Point-to-Point Protocol.
power-on self-test (POST). A series of diagnostics
that are automatically run by a device when the power
is turned on.
primary FCS switch. Primary fabric configuration
server switch. The switch that actively manages the
configuration and security parameters for all switches in
the fabric. See also backup FCS switch and FCS
switch .
primitive sequence. A part of an ordered set that
indicates or initiates port states. See also ordered set .
Glossary
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