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

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Glossary
downstream A term that refers to
the relative position of two stations
in a ring. A station is downstream of
its neighbor if it receives the token
after its neighbor receives the token.
dual homing A method of cabling
concentrators and stations that
permits an alternate or backup path
to the dual ring in case the primary
connection fails. Can be used in a
tree or dual ring of trees
configuration.
dual ring An FDDI network
topology that uses two redundant
rings to overcome fiber-optic failures
between two nodes.
dual ring of trees A topology of
concentrators and nodes that cascade
from concentrators on a dual ring.
E
ECM (Entity Coordination
Management) That portion of the
Connection Management (CMT)
within the Station Management
(SMT) function of an FDDI station
that provides for controlling bypass
relays, signaling to PCM (Physical
Connection Management) that the
medium is available, and
coordinating trace functions.
encapsulating bridge A
proprietary hardware device that
encapsulates packets into specialized
frames, usually by adding a header
and a trailer to the frame.
encode The act of changing data
into a series of electrical or optical
pulses that can travel efficiently over
a medium.
extended LAN A collection of
local area networks (similar or
dissimilar) interconnected with a
bridge.
F
FDDI (Fiber Distributed Data
Interface) An ANSI standard
(X3T9.5) for 100 Mbps LANs based
on the token-passing access method.
It is often used to bridge several
Ethernet segments at high speed.
fiber optic cable A transmission
medium designed to transmit digital
signals in the form of pulses of light.