The PRBS test is realized by that the OTU sends the PRBS code and monitors the PRBS code looped back from the local board or remote board. By comparing the PRBS code sent with the PRBS code looped back, the OTU can determine whether the current link or equipment is normal.
Prerequisites
The corresponding OTU boards must be created.
Opening the client-side laser of an OTU board.
Enable PRBS Test Status of the client-side and WDM-side ports of the tested board.
In the case of the ETMX/ETMXS board, pass-through or cross-connect services should be configured.
Background Information
The PRBS test described in this section is for test boards. For how to enable PRBS Test Status of the tested boards, refer to Configuring the PRBS Test Status of the Tested Board.
Precautions
- During a PRBS test, all services are interrupted. A PRBS test is used only in deployment. After the deployment, set PRBS Test Status to Disabled.
- During a PRBS test, users can only query configuration. No configuration can be delivered to boards.
Procedure
- In the NE Explorer, select a board and choose from the Function tree.
- Select a channel or a port in the PRBS Test interface, and set Duration and Measured in Time.
- Optional: Check the Accumulating Mode checkbox. The test result is displayed in the coordinates pane in an accumulative manner.
NOTE: In a cumulative mode, the bit error value in the n second is the sum of the bit errors in the previous n seconds.
- Click Start to Test. A dialog box indicating that this operation may interrupt the service is displayed. Click OK to start the PRBS test.
- After the test is complete, view the test result in the coordinates pane.
NOTE: - If the green histogram is displayed in the coordinates pane, the equipment is normally working.
- If the red histogram is displayed in the coordinates pane, bit errors exist on the line.
- If the yellow histogram is displayed in the coordinates pane, the line might be interrupted or have loud noise.