Digital Link DL3800 DS1, Руководство пользователя

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G-6 DL3800 DS1 Inverse Multiplexer User Guide—February 1999
G
bandwidth
The data-carrying capacity of a transmission medium, usually measured in
Hertz (Hz), which equals cycles per second.
baud
A measurement of the signaling speed of a data transmission device.
BER
See bit error rate.
BES (Bursty Errored Seconds)
Occurs when a second has 320 or more CRC violations. (ESF format only)
bipolar
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
Occurs when the value of an encoded bit is changed in transmission, and
interpreted incorrectly by the receiver.
Bit Error Rate (BER)
The percentage of received bits that are in error, relative to a speciÞc amount of
bits received; usually expressed as a number referenced to a power of 10.
bps
Bits per second; the basic unit of measure for serial data transmission capacity;
Kbits (kilobits) for thousands of bits per second; Mbitps (megabits) for millions
of bits per second, and Gbits (gigabits) for billions of bits per second.
Blue Alarm
An unframed sequence of All Ones normally sent by a DSU/CSU that cannot
maintain the required pulse density in AMI mode or sent by a CSU that has a
loss of signal condition on its data port. The signal is sent to maintain
continuity of transmission and to notify the far-end that a transmission fault
exists on the line. Same as Alarm Indication Signal (AIS).
broadband
Services or interfaces that operate above the T1 data rate, typically at NxT1, T3,
SONET, or ATM speeds.
BPV (Bi Polar Violation)
Occurs when the ones bit is not represented with the opposite signal of the
previous ones bit.