Installing and Administering HP EISA FDDI/9000 and HP HSC FDDI/9000

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Glossary
Management (SMT) function of an
FDDI station that periodically
announce their addresses to
downstream neighbors. Each station
in the ring makes such an
announcement every 30 seconds by
sending a NIF that uses Next Station
Addressing (NSA), a special
addressing mode that permits a
station to send a frame to the next
station on the token path without
knowing the address of that station.
This information can be used to
create a logical ring map for the
order in which each station appears
within the ring.
NMS (Network Management
Station) The system responsible
for managing a network or a portion
of a network. The NMS
communicates to network
management agents which reside in
the managed node using a network
management protocol.
node A device, such as a station or
concentrator, connected to a
network.
NRZ (Nonreturn to Zero) A
data transmission technique where a
polarity level, high or low, represents
a logical 1 or 0.
NRZI (Nonreturn to Zero
Invert on Ones) A data
transmission technique where a
polarity transition from low to high,
or high to low, represents a logical 1.
The absence of a polarity transition
represents a 0.
NSA (Next Station Addressing)
A special addressing mode in FDDI
networks that permits a station to
send a frame to the next station on
the token path without knowing that
station’s address.
O
optical receiver An opto-
electronic circuit that converts an
incoming optical signal to an
electrical signal, typically a
photodetector.
optical transmitter An opto-
electronic circuit that converts an
electrical signal to an optical signal,
typically a light emitting diode or a
laser diode.
OSI Model (Open Systems
Interconnection) The 7-layer
protocol model defined by the
International Standards Organization
(ISO) for data communications.