HP StorageWorks Fabric OS 5.0.0 Command Reference Guide (AA-RW1MA-TE, May 2005)

774 Glossary
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 the following items:
• Frame delimiters—Mark frame boundaries and describe frame contents.
• Primitive signals—Indicate events.
• Primitive sequences—Indicate or initiate port states.
Ordered sets are used to differentiate Fibre Channel control information from data frames and
to manage frame transport.
originator The Nx_Port that originated an exchange.
out-of-band Transmission of management protocol outside of the Fibre Channel network, usually over
Ethernet.
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.
PAL Programmable Array Logic. A relatively small FPD.
parallel The simultaneous transmission of data bits over multiple lines.
Participating Mode A mode in which an L_Port in a loop has a valid AL_PA and can arbitrate, send frames, and
retransmit received transmissions. See also L_Port, Nonparticipating Mode.
passive copper A low-cost copper Fibre Channel connection, allowing distances up to 13 meters between
devices.
path selection The selection of a transmission path through the fabric. HP switches use the FSPF protocol. See
also FSPF.
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.
PCM Pulse-code modulation. A standard method of encoding analog audio signals in digital form.
Performance
Monitoring
A HP switch feature that monitors port traffic and includes frame counters, SCSI read
monitors, SCSI write monitors, and other types of monitors.
persistent error log Error messages of a high enough level (by default, Panic or Critical) are saved to flash memory
on the switch instead of to RAM. These messages are saved over reboots and power cycles,
constituting the persistent error log. Note that each CP on a 2/64 has its own unique
persistent error log.
phantom address An 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.
phantom domain See xlate domain.
PID Port identifier.