Setting the NULL Mapping Status

Some OTU boards in the NG WDM equipment support the OTN NULL mapping detection. For the channel where no signals are input, the Web LCT can be used to set the NULL mapping status to Enabled. By checking OTN overheads, the channel status in the network can be monitored.

Prerequisites

The following OTU boards or tributary boards and line boards must be configured: LQMS, LQMD, LSX, NS2, LOG, LSC, TQX, TOA, THA, TMX, NQ2, NS3, LSXL and NO2.

Precaution

NOTICE:

The PRBS test and the NULL mapping test cannot be performed at the same time.

Context

Figure 1 shows the common networking mode for NULL mapping detection.

Figure 1 Networking diagram for NULL mapping test

Procedure

In the NE Explorer, select a board and choose Configuration > WDM Interface from the Function Tree.
Select the By Board/Port (Channel) radio button. Select Channel from the drop-down list.
Select the Advanced Attributes tab. Double-click the NULL Mapping Status and select Enabled.
Click Apply.
Start the NE Explorer of the opposite NE. Select a board and choose Configuration > OTN Overhead Management > OPU Overhead.
Check if the value of PT Received is the same as the PT to be received.