Glossary
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FC port An FC port is the opening at the back of a router that provides a fiber optic connection between
the FC adapter and FC host.
FC protocol for SCSI (FCP) FCP defines an FC mapping layer (FC-4) that uses FC-PH services to
transmit SCSI command, data, and status information between a SCSI initiator and SCSI target. FCP
enables transmission and receipt of SCSI commands, data, and status across the FC using standard FC
frame and sequence formats.
Fibre Fibre is a generic FC term that refers to all transmission media types specified in the FC Physical
Layer standard (FC-PH), such as optical fiber, copper twisted pair, and copper coaxial cable.
Fibre Channel (FC) FC is a bidirectional, point-to-point serial data channel, structured for high-
performance capability. In the physical sense, an FC is an interconnection of multiple communication
points, called N_Ports, by a switching network (fabric). FC transports incoming data from devices by
reading the buffer information, packaging it, and sending the information across the fabric. Although FC
is a generalized transport mechanism that has no protocol of its own or native I/O command set, it can
transport any existing upper-level protocol such as SCSI and IP. FC offers high-speed data transfer rates.
FC is most commonly used to connect clustered servers to storage systems. ANSI has developed
standards for FC.
gigabit interface converter (GBIC) A GBIC, also referred to as a Physical Link Module, is a physical
component that manages functions of the FC-0 layer. This layer consists of the physical characteristics
of the media and interface, including drivers, transceivers, connectors, and cables. A GBIC attaches to
an FC adapter and connects a router to an FC host.
high voltage differential (HVD) HVD is a differential SCSI scheme with terminators that run on 5 volts.
host bus adapter (HBA) An HBA is the critical link between a host server or workstation and a storage
Subsystem, integrating computing platforms, operating systems, and I/O protocols to ensure proper inter
operability and functionality. The bus adapter provides direct storage connectivity from the system to data
within the storage Subsystem and enables stable, high-speed transmission of information and files. HBAs
manage the controller-specific aspects of handling a storage driver interface device implemented as a
target driver, which supports mass storage peripheral devices such as disks and tapes. A storage driver
interface is used to implement SCSI and other storage device drivers. An HBA connects to the storage
Subsystem to the host computer and uses either fiber or copper media.
Hot plugging A device with the capability of being connected to a Subsystem without interrupting the
power supplies to that Subsystem.
Hot swap Hot swapping is the term used for manually swapping a failed disk unit with a replacement
while the Galaxy 65 Subsystem is in normal use.
Hz (Hertz) a frequency measurement unit used internationally to indicate cycles per second.
in-band Method of accessing and managing the SM controller or Galaxy 65 Subsystem using the SCSI
or FC host connection. This type of access is available using CAPI to develop a programmed interface.
Initialize To prepare a hardware device for use.
initiator An initiator is an FC or SCSI device that contains application clients that originate service
requests and task management functions for processing by a target FC or SCSI device.