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

resilient core/
edge topology
Two or more switches acting as a core to interconnect multiple edge switches.
Nodes attach to the edge switches.
See also edge switch.
responder The N_Port with which an exchange originator attempts to communicate.
retimer A circuit that uses an independent clock to generate outbound signals.
return loss The ratio expressed in decibels ) of incident power to reflected power, when a
component or a ssembly is introduced into a link or system. Can refer to optical
powerortoelectricalpowerinaspecified frequency range.
RLS Read Link Status.
route As it applies to a fabric, the communication path between two switches. It might
also apply to the specific path taken by an individual frame, from source to
destination.
See also FSPF.
routing The assignment of frames to specific switch ports, according to frame destination.
R_RDY Receiver ready. A primitive signal indicating that the port is ready to receive
aframe.
RR_TOV Resourc e recovery tim eout value. The minimum time a target device in a loop
waits after an LIP before log g ing out a SCSI initiator.
See also E_D_TOV and R_A_TOV.
RSCN Registered state change notification. A switch function that allows notification
of fabric changes to be sent from the switch to specified nodes. The fabric
controller issues RSCN requests to N _Ports and NL_Ports, but only if they have
registered to be notified of state changes that occur in other N_Ports and
NL_Ports. This registration is performed via the State Change Registration (SCR)
Extended Link Service. An N_Port or NL_Port can issue an RSCN to the fabric
controller without having completed SCR with the fabric controller.
R_T_TOV Receiver transmitter tim eout value. Used by receiver logic to detect loss of
synchronization between transmitters and receivers.
RTWR Reliable transport with response. Might appear as a task in portLogDump
command output.
running disparity A binary parameter indicating the cumulative disparity (positive or negative) of
all previously issued transmission characters.
RW Read/write. A term that refers to access rights.
RX An abbreviation for com munications term receive.
See also TX.
RX_ID Responder exchange identifier. A 2-byte field in the frame header that can be
used by the responder of the exchange to identify frames as being part of a
particular exchange.
SAN Storage area network. A network of systems and storage devices that
communicate using Fibre Channel protocols.
See also fabric.
SAN architecture The overall design of a storage network solution, which includes one or more
related fabrics, each of which has a topology.
SANportcount The number of ports available for connection by n od es in the entire SAN.
SCA Single connector attachment. A t ype of disk drive connector that is frequently
used for at taching SCSI drives to host systems.
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Glossary