HP Cisco MDS 9120 Cisco MDS 9124e Fabric Switch for HP c-Class BladeSystem Use - Page 62

R_A_TOV RAID request rate route routing RR_TOV RSCN SAN SDRAM sequence service rate single mode SNMP SNS switch switch port SWL tenancy throughput Resource allocation time-out value. The maximum time a frame can be delayed in the fabric and still be delivered. 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. The rate at which requests arrive at a servicing entity. With respect 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. The assignment of frames to specific switch ports according to frame destination. Resource recovery time-out value. The minimum time a target device in a loop waits after a LIP before logging out a SCSI initiator. Registered state change notification. A switch function that allows notification of fabric changes to be sent from the switch to the specified nodes. Storage area network. A network of systems and storage devices that communicate using FC protocols. Synchronous dynamic random access memory. The main memory for a switch. See also switch. A group of related frames transmitted in the same direction between two N_ports. The rate at which an entity can service requests. The fiber optic cabling standard that corresponds to distances up to 10 km between devices. Simple Network Management Protocol. An Internet management protocol that uses either IP for network-level functions and UDP for transport functions, or TCP/IP for both. SNMP can be made available over other protocols (such as UDP/IP) because it does not rely on the underlying communication protocols. See also MIB,trap (SNMP). Simple Name Server. 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. May also be referred to as a directory service. Hardware that routes frames according to FC protocol and is controlled by software. A port on a switch. Switch ports can be E_Ports, F_Ports, or FL_Ports. Short wavelength. A type of fiber optic cabling that is based on 850 mm lasers and supports link speeds up to 2 Gb/s. May also refer to the type of transceiver. The time span that begins when a port wins arbitration in a loop and ends when the same port returns to the monitoring state. Also called loop tenancy. The rate of data flow achieved within a cable, link, or system. Usually measured in bits per second (b/s). 62 Glossary