Ft1 Cable - H3C MSR 20-20 Command Reference Manual

Description
Example

ft1 cable

Syntax
View
Parameter
Description
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.
Use the command to start a BERT test on a T1-F interface.
ft1 bert
Use the
undo ft1 bert
interface.
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 at present.
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
checks the received pattern for bit error rate, and by so doing helps you identify
the condition of the line. To this end, 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.
# Run a 10-minute 2^20 BERT test on T1-F interface Serial 2/0.
<Sysname> system-view
[Sysname] interface serial 2/0
[Sysname-Serial2/0] ft1 bert pattern 2^20 time 10
ft1 cable { long decibel | short length }
undo ft1 cable
T1-F interface view
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. In this case, no external CSU is required.
short length: Matches a cable length shorter than 199.6 meters (655 feet). The
argument length can take 133ft, 266ft, 399ft, 533ft, or 655ft, depending on the
actual transmission distance.
Use the ft1 cable command to set the cable attenuation and length on the T1-F
interface.
Use the
undo ft1cable
command to stop the BERT test running on the T1-F
command to restore the default, that is, long 0db.
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