Fibre Channel

Logically, Fibre Channel is a bidirectional, full-duplex, point-to-point, serial data channel structured for high performance capability. Physically, the Fibre Channel is an interconnection of multiple communication ports, called NL_Ports, interconnected by a switching network, called a fabric, a point-to-point link or an arbitrated loop. Fibre Channel is a generalized transport mechanism that has no protocol of its own or native input/output command set, but can transport any existing Upper Level Protocols (ULPs) such as SCSI and IPI at speeds of 100 Mbytes/sec over distances of up to 10 kilometers over optical links. Fibre Channel can interconnect two devices in a point-to- point topology, from two to 126 devices in an arbitrated loop, and up to 224 devices in a fabric switched topology.

Fibre Channel Arbitrated Loop (FC-AL)

One of three existing Fibre Channel topologies in which two to 126 devices are interconnected serially in a single loop circuit without hubs and switches. Communication is managed using an arbitration process in which the lowest port address has the highest priority for communicating. The arbitrated loop topology supports all classes of service and guarantees in-order delivery of frames when the source and destination are on the same loop.

Link

For Fibre Channel, a connection between two nodes, each having at least one N_Port, interconnected by a pair of optical or copper links, one inbound and one outbound.

Long Wave

Lasers or LEDs that emit light with wave lengths around 1300 nm. Long-wave lasers are used for long Fibre Channel links, from 700 to 2000 meters. They are typically used with single-mode fiber of a 9-micron core size.

Loop Address

The unique ID of a node in Fibre Channel loop topology, sometimes referred to as a loop ID.

118Glossary