HP StorageWorks Fabric OS 5.X Master Glossary (AA-RW7NA-TE, September 2005)

public loop An arbitrated loop that includes a participating FL_Por t and can contain both
public and private NL_Ports.
public NL_Port An NL_Por t that logs in to the fabric, can functi
on within either a public or a
private loop, and can com mu nicate with either private or public NL_Ports.
QLA A type of Fibre Channel controller.
QLFA QuickLo op Fabric Assist. Arbitrated-loop technology.
See also arbitrated loop.
QoS Quality of service. A defined level of performance in a data communications
system. When data is broken into packets that travel through the same routers
in a LAN or WAN with all other data, QoS mechanisms are the only way to
guarantee quality by giving real-time data priority over non-real-time da ta.
queue A mechanism for each AL_PA address that allows for collecting frames prior
to sending them to the loop.
QuickLoop A software product that allows multiple ports on a switch to create a logical
loop. Devices connected via QuickLoop appear to each other as if they are
onthesamearbitratedloop.
QuickLoop Mode Amodethatallowsinitiatordevicestocommunicatewithprivateorpublic
devices that are not in the same loop.
radius The greatest distance between any edg e switch and the center of a fabric. A
low-radius net work is b etter than a high-radius net work.
RAID Redundant array of independent disks. A collection of disk drives that appear
as a single volume to the ser ver and are fault tolerant through mirroring or
parity checking.
See also JBOD.
RAIT Redundant a
rray of independent tapes. A collection of tape drives that appear
as a single volume to the server and are fault tolerant.
R_A_TOV Resource allocation timeout value. The maximum time a frame can be delayed
in the fabric and still be delivered.
See also E_D_TOV and RR_TOV.
RCS Reliable Commit Service. Refers to Brocade-speci fic ILS command code.
RCS_SFC RCS Stage Fabric Config. Refers to Brocade-specific I LS command code.
R_CTL Route control. The first 8 bits of the header, which defines the type of frame
and its contents.
receiver A device that performs detection and signal p rocessing.
redundancy Having multiple occurrences of a component to maintain high availability (HA).
Remote Switch An optionally licensed product for long-distance fabrics, requiring a Fibre
Channel-to-ATM or SO NET gateway.
repeater A circuit that uses a recovered clock to regenerate and transmit an outbound
signal.
request rate Therateatwhichrequestsarriveataservicingentity.
See also service rate.
resilience A fabric’s ability to adapt to or tolerate a failure of a component within the
fabric.
Fabric OS 5.x master glossary
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