Black Box SCAN-LAN VI, Manual

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GLOSSARY
Frequency — Rate of AC signal alternation, defined in Hertz (cycles per
second).
Full Duplex — Transmission of data in both directions at the same time.
Gateway — A device that interconnects two or more networks that may use
different protocols and media.
Hertz (Hz) — Unit of measure for frequency in cycles per second (cps).
Horizontal Cable — The part of a building’s cabling that extends from
and includes the telecommunications outlet in the work area to the
telecommunications (IDF) closet on the same floor.
Hub — A piece of LAN equipment that allows multiple network devices to
be connected to the network cabling system through a central point. Also
called a concentrator.
I/O — Input/Output.
IDF (Intermediate Distribution Frame) — The distribution point where
vertical backbone cable is connected to the horizontal cables.
IEEE — Institute of Electrical and Electronic Engineers.
Impedance — A frequency-dependent parameter defined by the ratio
of the AC Voltage to Current across a circuit element.
Impulse Noise — Non-repetitive electrical spikes or pulses caused by
external electromagnetic fields.
Inductance — The ability to store a magnetic field across a conductor
measured in Henries (H).
Insulation — A non-conductive material used to isolate conductor surfaces.
Internetworking — Communication among devices across multiple
networks.
ISO — International Organization for Standardization.
Jabber — A network fault condition where one station is continuously trans-
mitting or transmits illegal packets of length greater than 20 milliseconds.