Configuring the PRBS Test in the Cross-Connect Direction Initiated by the Tributary Board

This topic describes how to configure the PRBS test in the cross-connect direction initiated by the tributary board on the Web LCT. NE 1 is considered as an example.

Context

The configuration process is as follows:

Configure a cross-connect service on the tributary port to be tested.
Perform a corresponding loopback for the section to be tested. For the available loopbacks, see Figure 2.
Start the PRBS test in the cross-connect direction for the tributary port.
Determine the working status of the tested section according to the test result.

The following procedure describes how to configure the PRBS test by describing how to configure an inloop on a VC-4 path on the line board of NE 1.

Precautions

NOTICE:

When you set a loopback, make sure that no active service is running on the optical port or path on which a loopback needs to be performed. Otherwise, the active service is interrupted.

Procedure

Create and activate a VC-12 service from tributary port 1 of the PQ1 board of NE 1 to timeslot 1 in the second VC-4 path of optical port 1 on the N3SL16 board. In the NE Explorer, select the NE and choose Configuration > SDH Service Configuration from the Function Tree. For information on the procedure, see Creating SDH Services.
Set an inloop on the VC-4 path where the VC-12 service is carried on the line side of the VC-12 service.
1. the N3SL16 board from the Object Tree and choose VC4 Loopback from the shortcut menu.
2. When the VC4 Loopback dialog box is displayed, set the second VC-4 path to Inloop and click Apply.
3. When the Prompt dialog box is displayed, click OK.
4. When the Operation Result dialog box is displayed, click Yes.
Select the PQ1 board from the Object Tree and choose Configuration > PRBS Test from the Function Tree.
Select the SDH_TU-1 port and set the following parameters in the Set Test Parameters area:
- Direction: Cross
- Duration: 10
- Measured in Time: s
- In the case of the other parameters, use the default values.
Click Start to Test. When the Operation Result dialog box is displayed, click Yes.
When Progress field is displayed as 100%, check the value in Total PRBS field.
- If the value is 0, that no bit errors are detected in the test and the tested loop is normal.
- If the value is not 0, the value indicates the number of bit errors detected in the test. In this case, you need to analyze the causes of the bit errors and perform troubleshooting.