PairGain CRA-C, Руководство пользователя

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Glossary
74 Megabit Modem CRA-C User Manual
CAP Carrierless Amplitude Phase Modulation. A two-
dimensional line code used in ADSL.
Crosstalk Line noise that occurs due to coupling of signals
between pairs in the same bundle.
Downstream The direction of data reception from the Megabit
Modem CRA-C to a remote unit.
Ethernet A baseband LAN specification that has become a
series of standards produced by IEEE referred to as
IEEE 802.3.
HDLC High-level Data Link Control.
Hub A common wiring point for star-topology networks,
and a common synonym for a concentrator.
IEEE Institute of Electrical and Electronics Engineers.
A professional organization that defines network
standards.
I/F Interface or Interface Card.
ISP Internet service provider.
kbps Kilobits per second. A measure of transmission
speed at 1,000 bits per second.
kpps Kilo packets per second.
LAN Local Area Network. The means by which a local
community of users and workgroups can share
information and resources electronically.
LED Light emitting diode.
Line code Any method of converting digital information to
analog form for transmission on a communicaton
line.
Link Another term used for transmission line.
MAC Media Access Control. Associated with Layer 2
or the Data Link Layer of the ISO 7-layer
protocol model.
Margin An ADSL parameter, measured in dB. It indicates
the excess SNR, relative to the performance of 10
–7
BER, at the receiver point.