3Com MSR 50, MSR 30 Ft1 cable, Syntax ft1 cable long decibel short length Undo ft1 cable, 243

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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.

Description Use the ft1 bert command to start a BERT test on a T1-F interface.

Use the undo ft1 bert command to stop the BERT test running on the T1-F 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.

Example # 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

Syntax ft1 cable { long decibel short length }

undo ft1 cable

View T1-F interface view

Parameter 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.

Description Use the ft1 cable command to set the cable attenuation and length on the T1-F interface.

Use the undo ft1cable command to restore the default, that is, long 0db.