IBM TotalStorage 3534-F08, Installation And User Manual

Page: 87 / 105

field replaceable unit (FRU). An assembly that is
replaced in its entirety when any one of its components
fails. In some cases, a field replaceable unit may
contain other field replaceable units.
File Transfer Protocol (FTP). In TCP/IP, an
application protocol used for transferring files to and
from host computers.
fill word. A transmission word that is an IDLE or an
ARBx primitive signal. Fill words are transmitted
between frames, primitive signals, and primitive
sequences to keep a Fibre Channel network active.
firmware. Proprietary code that is usually delivered as
microcode as part of an operating system. Firmware is
more efficient than software loaded from an alterable
medium and more adaptable to change than pure
hardware circuitry. An example of firmware is the Basic
Input/Output System (BIOS) in read-only memory
(ROM) on a PC system board.
FLOGI. See fabric login.
FL_port. See fabric loop port.
F_port. See fabric port.
frame. In Fibre-channel technology, the structure used
to transmit data between ports. A frame consists of a
start-of-frame delimiter, header, any optional headers,
the data payload, a cyclic redundancy check (CRC),
and an end-of-frame delimiter. There are two types of
frames: link control frames (transmission
acknowledgements, and so on) and data frames.
FRU. See field replaceable unit.
FS. See Fibre-channel service.
FSP. See Fibre Channel Service Protocol.
FSPF. See Fibre-channel shortest path first.
FTP. See File Transfer Protocol.
full-duplex. Describing a communications connection
over which each device can transmit and receive
simultaneously. See also half-duplex.
Fx_port. A fabric port that can operate as either a
fabric port (F_port) or fabric loop port (FL_port). See
also fabric port and fabric loop port.
gateway. A functional unit that interconnects two
computer networks with different network architectures.
A gateway connects networks or systems of different
architectures. A bridge interconnects networks or
systems with the same or similar architecture.
GBIC. See gigabit interface converter.
generic port (G_port). A port on a Fibre Channel
switch that can function either as a fabric port (F_port)
or as an expansion port (E_port). The functionality of a
G_port is determined during port login. A G_port
functions as an F_port when connected to a node port
(N_port), and as an E_port when connected to an
E_port.
gigabit interface converter (GBIC). A transceiver that
converts between electrical signals used by host bus
adapters (and similar Fibre Channel and Ethernet
devices) and either electrical or optical signals suitable
for transmission. Gigabit interface converters allow
designers to design one type of device and adapt it for
either copper or optical applications. Unlike gigabaud
link modules, GBICs can be hot-swapped.
gigabit switch. A 16-port, Fibre-channel gigabit
switch.
G_port. See generic port.
graphical user interface (GUI). A type of computer
interface that presents a visual metaphor of a real-world
scene, often of a desktop, by combining high-resolution
graphics, pointing devices, menu bars and other menus,
overlapping windows, and the object-action relationship.
GUI. See graphical user interface.
half-duplex. Describing a communications connection
over which only one device at a time can transmit data.
See also full-duplex.
hard address. The arbitrated loop physical address
(AL_PA) that a node loop port (NL_port) attempts to
acquire during loop initialization.
hardware translative mode. A method for achieving
address translation. Two hardware translative modes
are available to a QuickLoop-enabled switch: Standard
Translative Mode, which allows public devices to
communicate with private devices across the fabric; and
QuickLoop Mode, which allows private devices to
communicate with other private devices across the
fabric.
HBA. See host bus adapter.
high availability. An attribute of the switch that
identifies it as being capable of operating well in excess
of 99 percent of the time. High availability is typically
identified by the number of nines in that percentage. For
example, a switch that is rated at five nines would be
capable of operating 99.999 percent of the time without
failure.
host bus adapter (HBA). The interface card between
a server or workstation bus and the Fibre-channel
network.
hub. A Fibre Channel device that connects nodes into
a logical loop by using a physical star topology. Hubs
will automatically recognize an active node and insert
Glossary
65