User Manual

260 Glossary
R_CTL
Route control. The first eight bits of the header, which defines the type of frame and its contents.
R_RDY
Receiver ready. A primitive signal indicating that the port is ready to receive a frame.
R_T_TOV
Receiver transmitter timeout value, used by receiver logic to detect loss of synchronization between transmitters and
receivers.
RAID
Redundant array of independent disks. A collection of disk drives that appear as a single volume to the server and
are fault tolerant through mirroring or parity checking. See also JBOD.
RCS
Reliable Commit Service.
remote switch
An optional product for long-distance fabrics, requiring a Fibre Channel-to-ATM or SONET gateway.
responder
The N_Port with which an exchange originator wishes to communicate.
RLS
Read Link Status.
route
As applied to a fabric, the communication path between two switches. May 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.
RR_TOV
Resource recovery timeout value. The minimum time a target device in a loop waits after a LIP before logging out an
SCSI initiator. See also E_D_TOV, 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 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.
RTWR
Reliable transport with response. May appear as a task in portlogdump command output.
running disparity
A binary parameter that indicates the cumulative disparity (positive or negative) of all previously issued transmission
characters.