R3303-HP HSR6800 Routers Interface Command Reference

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2^20: Specifies the length of transmitted BERT pattern, in bits, as two to the twentieth power.
time minutes: Sets the duration (in minutes) of a BERT test. The minute argument is up to 1,440.
unframed: Sets the test pattern to cover the overhead bits of the frame.
Usage guidelines
ITU O.151, ITU O.153, and ANSI T1.403-1999 define many BERT patterns, among which, the T1-F
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 somewhere on the
line and sent back to the local end. The local end then checks 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 ft1 serial command.
Examples
# Run a 10-minute 2^20 BERT test on T1-F interface Serial 2/0/0.
<Sysname> system-view
[Sysname] interface serial 2/0/0
[Sysname-Serial2/0/0] ft1 bert pattern 2^20 time 10
ft1 cable
Use ft1 cable to set the cable attenuation and length on a T1-F interface.
Use undo ft1cable to restore the default.
Syntax
ft1 cable { long decibel | short length }
undo ft1 cable
Default
The cable attenuation length is long 0db.
Views
T1-F interface view
Default command level
2: System level
Parameters
long decibel: Matches 199.6-meter (655-feet) and longer cable length. The argument decibel can take
0db, -7.5db, -15db, or -22.5db, depending on the signal quality at the receiving end. No external CSU
is required.
short length: Matches a cable length shorter than 199.6 meters (655 feet). The argument length can take
133f t, 266ft, 399ft, 533ft, or 655ft, depending on the actual transmission distance.
Usage guidelines
You may use this command to adapt the signal waveform to different transmission conditions such as the
quality of the signal received by the receiver. If signal quality is good, use the default setting.