IBM 3534-F08 Installation And User Manual page 85

CMI. See control message interface.
comma. A unique pattern (either 1100000 or 0011111)
used in 8B/10B encoding to specify character alignment
within a data stream. See also K28.5.
community. The relationship between a Simple
Network Management Protocol (SNMP) agent and one
or more SNMP managers. The community describes
which SNMP manager requests that the SNMP agent
should honor.
control message interface (CMI). A set of control
signals that are used to pass hardware-level messages
between ports.
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.
cut-through. A switching technique that allows a
routing decision to be made and acted upon as soon as
the destination address of a frame is received. See also
route.
cyclic redundancy check (CRC). 1) A redundancy
check in which the check key is generated by a cyclic
algorithm. 2) An error detection technique performed at
both the sending and receiving stations.
data word. A type of transmission word that occurs
within frames. The frame header, data field, and CRC
all consist of data words. See also frame, ordered set,
and transmission word.
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 enabled zone configuration and zone
configuration.
destination ID (DID). The 3-byte destination ID of the
destination device, in the 0xDomainAreaALPA format.
DID. See destination ID.
direct memory access (DMA). The transfer of data
between memory and an input/output (I/O) device
without processor intervention.
disparity. The relationship of ones and zeros in an
encoded character. Neutral disparity indicates an equal
number of ones and zeros, positive disparity indicates a
majority of ones, and negative disparity indicates 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
value of domain_ID can be a value between 1- 239.
DRAM. See dynamic random access memory.
dynamic load sharing (DLS). A dynamic distribution
of traffic over available paths that permits recomputing
of routes when an 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 of 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.
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.
end-to-end credit (EE_credit). A credit scheme used
to manage end-to-end flow control during the exchange
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Glossary