Technical data

Glossary-10
multimode A fiber optic cabling specification that allows up to 500 meters between devices.
N
N_Port Node 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. See also NL_Port, Nx_Port.
Name Server Simple Name Server (SNS). A switch service that stores names, addresses, and attributes for up to 15
minutes and provides them as required to other devices in the fabric. SNS is defined by Fibre Channel
standards and exists at a well-known address. Also referred to as "directory service."
NAS Network-attached storage. A disk array connected to a controller that gives access via a LAN.
NIC Network interconnect card.
NL_Port Node loop port. A node port that has arbitrated-loop capabilities. Used to connect an equipment port to
the fabric in a loop configuration through an FL_Port. See also N_Port, Nx_Port.
node A Fibre Channel device that contains an N_Port or NL_Port.
node count The number of nodes attached to a fabric.
node name The unique identifier for a node, communicated during login and port discovery.
NR_Port A normal E_Port used to connect an FC Router to a backbone fabric.
NS Name Server. The service provided by a fabric switch that stores names, addresses, and attributes
related to Fibre Channel objects. Can cache information for up to 15 minutes. Also known as "Simple
Name Server" or as a "directory service." See also Simple Name Server (SNS).
Nx_Port A node port that can operate as either an N_Port or NL_Port.
O
oversub-
scription
A situation in which more nodes could potentially contend for a resource than the resource could
simultaneously support (typically an ISL). Oversubscription could be a desirable attribute in fabric
topology, as long as it does not produce unacceptable levels of congestion.
OX_ID Originator ID or exchange ID. Refers to the exchange ID assigned by the originator port.
P
payload A Fibre Channel frame has a header and a payload. The payload contains the information being
transported by the frame; it is determined by the higher-level service or FC_4 upper-level protocol.
There are many different payload formats, based on protocol.
PBC Port bypass circuit. A circuit in hubs or a disk enclosure to open or close a loop to add or remove nodes.
PCBA Printed circuit board assembly.