Digital Link DL600E, Руководство пользователя

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Glossary
A
All 1s
ÑAll Ones simulates the highest spectral components and highest energy
out of the product and out of the line repeaters on the E1 line.
All 0s
ÑA pattern that checks the correct operation of the HDB3 (E1) line cod-
ing. This code is meant to allow a pattern with many 0 bits to go through the
line transparently.
attenuation
Ñ Reduction or loss of signal strength, measured in decibels;
opposite of gain.
B
bandwidth
Ñ The data-carrying capacity of a transmission medium, usually
measured in Hertz (Hz), which equals cycles per second.
bipolar
Ñ The predominant signaling method used for digital transmission
services, such as DDS and T1 , in which the signal carrying the binary value
successively alternates between positive and negative polarities. Zero and
one values are represented by the signal amplitude at either polarity, while no
value ÒspacesÓ are at zero amplitude.
bit error
ÑOccurs when the value of an encoded bit is changed in transmis-
sion, and interpreted incorrectly by the receiver.
broadband
ÑServices or interfaces that operate above the T1 data rate, typi-
cally at NxT1, T3, SONET, or ATM speeds.
C
central ofÞce (CO)
ÑThe phone company switching facility or center; usually
a Class 5 end ofÞce, at which subscribers' local loops terminate.
channel
Ñ A physical or logical path allowing the transmission of informa-
tion; the path connecting a data source and receiver.