IBM 3534-F08 Installation And User Manual page 89

looplet. A set of devices connected in a loop to a port
that is a member of another loop.
loop master timeout value (LM_TOV). The minimum
time that the loop master waits for a loop initialization
sequence to return.
loop port (L_port). A port used to connect a node to a
Fibre Channel Arbitrated Loop (FC-AL). See also
non-participating mode and participating mode.
loop port state machine (LPSM). The logical entity
that performs arbitrated loop protocols and defines the
behavior of loop ports (L_ports) when they require
access to an arbitrated loop.
L_port. See loop port.
LPSM. See loop port state machine.
LUN. See logical unit number.
LWL. See long wavelength.
MAC. See media access control.
management information base (MIB). A definition for
management information that specifies the information
available from a host or gateway and the operations
allowed.
master port. As relates to trunking, the port that
determines the routing paths for all traffic flowing
through the trunking group. One of the ports in the first
ISL in the trunking group is designated as the master
port for that group. See also ISL Trunking.
media access control (MAC). Algorithms that control
access to physical media, especially in shared media
networks.
MIB. See management information base.
multicast. Transmission of the same data to a
selected group of destinations. See also broadcast and
unicast.
multimode. A type of optical fiber which incorporates
shortwave lasers and which is used with gigabaud link
modules. Typically, it is used for links of up to 500 m
(1640.42 ft).
name server. In networking, the server that translates
network names to addresses. See also simple name
server.
NL_port. See node loop port.
node. A Fibre-channel device that contains a node
port (N_port) or node loop port (NL_port).
node loop port (NL_port). A port specific to Fibre
Channel Arbitrated Loop (FC-AL). An NL_port has the
same functional, logical, and message handling
capability as a node port (N_port), but connects to an
arbitrated loop rather than to a fabric. Some
implementations can function either as N_ports or as
NL_ports depending on the network to which they are
connected. An NL_port must replicate frames and pass
then on when in passive loop mode.
node name. The name assigned to a node during
network definition.
node port (N_port). A port that connects a node to a
fabric or to another node. N_ports connect to fabric
ports (F_ports) or to other N_ports of other nodes.
N_ports handle creation, detection, and flow of message
units to and from the connected systems. N_ports are
end points in point-to-point links.
non-participating 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 storage (NVS). A storage device whose
contents are not lost when power is cut off.
N_port. See node port.
NVRAM. Nonvolatile storage random access memory.
See nonvolatile storage.
NVS. See nonvolatile storage.
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.
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, which mark frame boundaries and describe
frame contents; primitive signals, which indicate events;
and primitive sequences, which indicate or initiate port
states. Ordered sets are used to differentiate Fibre
Channel control information from data frames and to
manage the transport of frames.
packet. In networking, a group of bits that has a
defined format and fixed maximum size, sent as a unit
across a network. See also frame.
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
non-participating mode.
path selection. The selection of a transmission path
through the fabric. Switches use the Fibre Channel
shortest path first (FSPF) protocol.
67
Glossary