R3303-HP HSR6800 Routers Interface Command Reference

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Usage guidelines
ITU O.151, ITU O.153, and ANSI T1.403-1999 define many BERT patterns, among which, the CT1
interface supports only 2^15 and 2^20.
When running a BERT test, the local end sends out a pattern, which is to be looped over somewhere on
the line and back to the local end. The local end then examines the received pattern for bit error rate to
help you identify the condition of the line. You must configure loopback to allow the transmitted pattern
to loop back from somewhere on the line, for example, from the far-end interface by placing the interface
in a far-end loopback.
You may view the state and result of the BERT test with the display controller t1 command.
Examples
# Run a 10-minute 2^20 BERT test on CT1 interface t1 2/0/0.
<Sysname> system-view
[Sysname] controller t1 2/0/0
[Sysname-T1 2/0/0] bert pattern 2^20 time 10
cable (CT1 interface)
Use cable to set the cable attenuation and length on the CT1 interface.
Use undo cable to restore the default.
Syntax
cable { long { 0db | -7.5db | -15db | -22.5db } | short { 133f t | 266ft | 399ft | 533ft | 655ft } }
undo cable
Default
The cable length is long 0db.
Views
CT1 interface view
Default command level
2: System level
Parameters
long: Matches 199.6-meter (655-feet) and longer cable length. The options for this parameter include
0db, -7.5db, -15db and -22.5db. The attenuation parameter is selected depending on the signal quality
received at the receiving end. No external CSU is needed.
short: Matches a cable length shorter than 199.6 meters (655 feet). The options for this parameter
include 133 ft, 266ft, 399ft, 533ft and 655ft. The length parameter is selected depending on the actual
transmission distance.
Usage guidelines
You may use this command to adapt signal waveform to different transmission conditions such as the
quality of the signal received by the receiver. If the signal quality is good, you can use the default setting.
The CT1 interface does not need an external CSU device.
Examples
# Set the cable length to 40.5 meter (133 feet) on CT1 interface T1 2/0/0.