IBM F16, Руководство пользователя

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control message interface (CMI). A set of control
signals that are used to pass hardware-level messages
between ports.
control processor (CP). The central processing unit
that provides all control and management functions in a
switch.
CP. See control processor .
CPLD. Complex programmable logic device.
CPU. See central processing unit .
CRC. See cyclic redundancy check .
credit. The number of receive buffers allocated to a
transmitting node port (N_port), node loop port
(NL_port), or fabric port (F_port). The credit is the
maximum number of outstanding frames that can be
transmitted by that N_port, NL_port, or F_port without
causing a buffer overrun condition at the receiver.
cyclic redundancy check (CRC). A check for
transmission errors included in every data frame.
data rate. The rate at which data is transmitted or
received from a device. Interactive applications tend to
require a high data rate, while batch applications can
usually tolerate lower data rates.
DDR. Double data rate. See data rate .
defined zone configuration. The complete set of all
zone objects that are defined in the fabric. The defined
configuration may include multiple zone configurations.
See also
zone configuration .
destination ID (DID). The 3-byte destination ID of the
destination device, in the 0xDomainAreaALPA format.
device. Hosts and storage that connect to a switch.
Example devices are servers, redundant array of
independent disks (RAID) arrays, and tape subsystems.
DID. See destination ID .
direct memory access (DMA). The transfer of data
between memory and an input/output (I/O) device
without processor intervention.
disk operating system (DOS). An operating system
for personal computers that can only perform tasks one
at a time.
disparity. The relationship of ones and zeros in an
encoded character. Neutral disparity means an equal
number of each, positive disparity means a majority of
ones, and negative disparity means a majority of zeros.
DLS. See dynamic load sharing .
DMA. See direct memory access .
domain_ID. A unique identifier for the switch in a
fabric. The domain_ID is usually automatically assigned
by the switch, but can also be assigned manually. The
values of domain_ID can be a value between 1- 239.
DOS. See disk operating system .
DRAM. See dynamic random access memory .
DWDM. Dense wavelength digital multiplexing.
dynamic load sharing (DLS). Dynamic distribution of
traffic over available paths. Allows for recomputing of
routes when a fabric port or fabric loop port (Fx_port) or
expansion port (E_port) changes status.
dynamic random access memory (DRAM). A
storage in which the cells require repetitive application
of control signals to retain stored data.
E_D_TOV. See error detect timeout value .
EE_credit. See end-to-end credit .
effective configuration. The particular zone
configuration that is currently in effect. Only one
configuration can be in effect at once. The effective
configuration is built each time a zone configuration is
enabled.
EIA. Electronic Industry Association.
EIA rack. A storage rack that meets the standards set
by the Electronics Industry Association (EIA).
electromagnetic compatibility (EMC). The design
and test of products to meet legal and corporate
specifications dealing with the emissions and
susceptibility to frequencies in the radio spectrum.
Electromagnetic compatibility is the ability of various
electronic equipment to operate properly in the intended
electromagnetic environment.
electromagnetic interference (EMI). Waves of
electromagnetic radiation, including but not limited to
radio frequencies, generated by the flow of electric
current.
electrostatic discharge (ESD). The flow of current
that results when objects having a static charge come
into close enough proximity to discharge.
ELP. Extended link parameters.
ELWL. See extra long wavelength .
EMC. See electromagnetic compatibility .
EMI. See electromagnetic interference .
enabled zone configuration. The currently enabled
configuration of zones. Only one configuration can be
enabled at a time. See also
defined zone configuration
and zone configuration .
Glossary
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