IBM Nways 2216, Руководство по обслуживанию и ремонту

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F
FANB. Fan box.
FAT. File allocation table.
fax. Hardcopy received from a facsimile machine.
Synonymous with
telecopy.
FDDI. Fiber distributed data interface (100 Mbps fiber
optic LAN)
FEP. Front-end processor.
flash memory. A data storage device that is
programmable, erasable, and does not require
continuous power. The chief benefit of flash memory
over other programmable and erasable data storage
devices is that it can be reprogrammed without being
removed from the circuit board.
FR. Frame relay.
FRAD. Frame relay assembler/disassembler.
frame relay. (1) An interface standard describing the
boundary between a user's equipment and a fast-packet
network. In frame-relay systems, flawed frames are
discarded; recovery comes end-to-end rather than
hop-by-hop. (2) A technique derived from the
integrated services digital network (ISDN) D channel
standard. It assumes that connections are reliable and
dispenses with the overhead of error detection and
control within the network.
frequency. The rate of signal oscillation, expressed in
hertz.
FRFH. Frame relay frame handler.
front-end processor (FEP). A processor, such as the
IBM 3745 or 3174, that relieves a main frame from the
communication control tasks.
FRTE. Frame relay terminal equipment.
FRU. Field replaceable unit.
FTP. File Transfer Protocol.
G
gateway. (1) 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 architectures. (T)
(2) In the IBM Token-Ring Network, a device and its
associated software that connect a local area network
to another local area network or a host that uses
different logical link protocols.
Gbps. Gigabits per second (1 000 000 000 bits per
second).
GUI. Graphical user interface.
H
HDLC. High-level data link control.
high-level data link control (HDLC). An access
service used over data networks. It uses a
non-real-time connection.
HDLC-like data link control, for example:
¹
Synchronous data link control (SDLC) used with
SNA, or
¹
Link access procedure for D-channel (LAP-D) used
with ISDN.
high-performance file system (HPFS). In the OS/2
operating system, an installable file system that uses
high-speed buffer storage, known as a cache, to
provide fast access to large disk volumes. The file
system also supports the coexistence of multiple, active
file systems on a single personal computer, with the
capability of multiple and different storage devices. File
names used with the HPFS can have as many as 254
characters.
high-performance routing (HPR). An addition to the
Advanced Peer-to-Peer Networking (APPN) architecture
that enhances data routing performance and reliability,
especially when using high-speed links.
hot pluggable. Refers to an hardware component that
can be installed or removed without disturbing the
operation of any other resource that is not connected to,
or dependant on, this component.
HPDT. High-Performance Data Transfer.
HPFS. High-performance file system.
HS. High-speed.
HSA. High-speed adapter (module).
HSDS. High-Speed Digital Services.
HSSI. High-speed serial interface.
hub (intelligent). A wiring concentrator, such as the
IBM 8260, that provides bridging and routing functions
for LANs with different cables and protocols.
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2216 Maintenance Manual