IBM TotalStorage 3534-F08, Installation Manual

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G_port when it is not yet connected or has not yet
assumed a specific function in the fabric.
gigabit interface converter (GBIC). A removable
serial transceiver module designed to provide gigabaud
capability for fibre channel (FC) and other products that
use the same physical layer.
gigabit switch. A 16-port, fibre-channel gigabit switch.
G_port. See generic port.
half-duplex. A mode of communication that allows a
port to either transmit or receive frames at any time, but
not simultaneously (with the exception of link control
frames, which can be transmitted at any time). See also
full-duplex.
hard address. The AL_PA that an NL_port attempts to
acquire during loop initialization.
hardware translative mode. Method for achieving
address translation. The following two hardware
translative modes are available to a QuickLoop-enabled
switch:
v
Standard Translative Mode: Allows public devices to
communicate with private devices across the fabric.
v QuickLoop Mode: Allows private devices to
communicate with other private devices across the
fabric.
HBA. See host bus adapter.
host bus adapter (HBA). The interface card between
a server or workstation bus and the fibre-channel
network.
hub. A fibre-channel wiring concentrator that collapses
a loop topology into a physical star topology. Nodes are
automatically added to the loop when active and
removed when inactive.
ID. Identification.
IDB. Interface descriptor block.
IDLE. Continuous transmission of an ordered set over
a fibre-channel link when no data is being transmitted,
to keep the link active and maintain bit, byte, and word
synchronization.
IETF. Internet Engineering Task Force.
information unit (IU). A set of information as defined
by either upper-level process protocol definition or
upper-lever protocol mapping.
initiator. A server or workstation on a fibre-channel
network that initiates communications with storage
devices. See also target.
in-order delivery (IOD). A parameter that, when set,
guarantees that frames are either delivered in order or
dropped.
integrated fabric. The fabric created by six switches
cabled together and configured to handle traffic as a
seamless group.
internet protocol (IP). In the Internet suite of
protocols, a connectionless protocol that routes data
through a network or interconnected networks and acts
as an intermediary between the higher protocol layers
and the physical network.
inter-switch link (ISL). A fibre link between two
switches.
IOD. See in-order delivery.
IP. See internet protocol.
IPA. Initial process associator.
ISL. See inter-switch link.
ISL Trunking. A feature that enables distribution of
traffic over the combined bandwidth of up to four ISLs
(between adjacent switches), while preserving in-order
delivery. A set of trunked ISLs is called a trunking group;
each port employed in a trunking group is called a
trunking port. See also master port.
isolated E_port. An E_port that is online but not
operational between switches due to overlapping
domain ID or nonidentical parameters such as
E_D_TOVs. See also expansion port.
IU. See information unit.
JBOD. See just a bunch of disks.
just a bunch of disks (JBOD). Indicates a number of
disks connected in a single chassis to one or more
controllers. See also redundant array of independent
disks.
K28.5. A special 10-bit character used to indicate the
beginning of a transmission word that performs fibre
channel control and signaling functions. The first seven
bits of the character are the comma pattern. See also
comma.
LAN. See local area network.
latency. The period of time required to transmit a
frame, from the time it is sent until it arrives.
LED. See light-emitting diode.
light-emitting diode (LED). A semiconductor chip that
gives off visible or infrared light when activated.
Glossary
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