Fujitsu PRIMEPOWER650, Руководство пользователя

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U41261-J-Z816-4-76 153
Glossary
MAC (Media Access Control)
Address
A physical (hardware) address that uniquely
identifies each node of a network. For IEEE
802.3 and Ethernet networks, it is defined as 48
bits long, with the first 24 bits being the OUI, a
unique hardware manufacturer's ID assigned
by the IEEE, and the final 24 bits assigned as
each manufacturer sees fit. The absolute
uniqueness of each MAC address is an
important feature, and the ROM or EPROM in
most LAN devices contains such a MAC
address, preventing the LAN from being
illicitly modified. A MAC address is usually
represented as a string of six hexadecimal
octets: 00-40-41-84-2B-2C or
00:40:41:84:2B:2C.
Memory Dump
The raw contents of a specified section of the
main memory, output in hexadecimal (or the
ASCII equivalent thereof) for use in
debugging.
Memory Interleaving
For speedier memory access, blocking due to
wait states can be reduced by splitting the main
memory into multiple banks, making areas of
memory other than that currently being
addressed more accessible. This is effective for
sequential memory accesses, but gives no
advantage for random accesses.
Mirroring
Modern hard disks are highly reliable, but even
so a variety of methods are used to ensure the
survival of your vitally important data, even if
a disk failure does happen. One of the simplest
methods is mirroring, which basically involves
keeping two copies of all data saved to the hard
disk. In this way, even if one copy is lost, the
other will remain, ensuring that no data is lost.
Parity Checking
A method of checking the integrity of
transmitted or stored data. The number of ones
or zeroes in a binary data segment is used to
calculate a parity bit which is appended to that
piece of data. If the same calculation at a later
time produces a parity bit that does not match
the previously assigned parity bit, the value of
at least one of the bits has changed, and the data
can be rejected as corrupt. This works if only 1
(or other odd number) bit changes, but if 2 bits
(or other even number) bits change then the
calculated parity bit will match the previously
assigned parity bit, meaning the errors will not
be detected. This means that while parity can be
used if errors are infrequent (and hence the
probability of two errors is minuscule), it
should be avoided if errors are rather more
common.
PCI (Peripheral Component
Interconnect)
An IEEE standard interface.
PCI Bus #
PCI slots listed as having the same PCI Bus
number will share CPU access over the same
PCI bus.
RCI (Remote Cabinet Interface)
A standard method of connecting multiple
hosts to multiple I/O devices. The RCI provides
power on/off, system control, system
monitoring, inter-host communication, and
various other functions.
RCI Node Address
A logical address assigned to each node of an
RCI network.
Redundant configuration
The provision of multiple interchangeable
components to perform a single function in
order to avoid a single point of failure.