4000 Router Series Interface Configuration Guide

Step Command Remarks

22. (Optional.) Restore the default

settings for the T1-F interface.

default N/A

23. Bring up the T1-F interface.

undo shutdown By default, a T1-F interface is up.

Starting/terminating a BERT test on a T1-F interface

BERT is operating as follows:

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 the bit error rate, and by so doing helps you

determine whether the condition of the line is good. 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 far-end loopback.

You can view the state and result of the BERT test with the display ft1 serial command.

To start/terminate a BERT test on a T1-F interface:

Step Command Remarks

1. Enter system view.

system-view N/A

2. Enter T1-F interface view.

interface serial interface-number N/A

3. Start a BERT test.

ft1 bert pattern { 2^20 | 2^15 }

time minutes [ unframed ]

By default, no BERT test is

performed.

Displaying and maintaining T1-F interfaces

Execute display commands in any view and reset commands in user view.

Task Command

Display information about a specified or all T1-F

interfaces.

display ft1 [ serial interface-number ]

Display the status of a specified T1-F interface. display interface serial interface-number

Clear the controller counter of a T1-F interface. reset counters interface [ serial [ interface-number ] ]

Configuring a CE3 interface

Overview

E3 belongs to the digital carrier system of ITU-T. It transmits data at 34.368 Mbps and adopts HDB3 as

the line code format.

A CE3 interface can operate in either E3 or CE3 (the default) mode.