An OTU1 service is available between one NG WDM TMX board and the LH WDM ETMX board. In this case, perform a cold reset on the NG WDM TMX board. When the TMX starts up, the service is available. The LH WDM ETMX board, however, reports the OUT_LOM alarm and the NG WDM TMX reports the Client_SD alarm.
1. The WDM-side ODU1 channels on the TMX and LH TMX boards scramble signals, and the WDM-side ODU1 channel on the LH ETMX board does not scramble signals.
2. The NG_TMX connects to the LH_ETMX on the WDM side. As the WDM-side ODU1 channels of the two boards are different in scrambling mode, the descrambling of the WDM-side ODU1 channel fails, and the ODU1_LOM alarm occurs. To ensure that the interconnection between the NG_TMX board and the LH_ETMX board is successful, the TMX board changes its ODU1 scrambling mode when discovering that the opposite board is an LH board and ODU1_LOM alarms exist in the WDM-side ODU1 channel of the LH board.
3. When the TMX board starts up after the cold reset, the WDM-side ODU1 channel scrambles signals. The WDM-side ODU1 channel of the opposite board (the LH_ETMX board) does not scramble signals. One ODU1 service is scrambled once at the client-side. Then, the ODU1 service returns to the input of port IP3 through the optical fiber and it is descrambled. The descrambling fails and OUT_LOM alarms occur. At the same time, the Client_SD alarm is inserted and the TMX board reports the Client_SD alarm.
4. On the opposite LH_ETMX board, one ODU1 service is input from the WDM-side, output from the client-side, and transported back to the TMX through the WDM-side. In this case, the TMX on the WDM-side successfully scrambles signals and the service is normal. The TMX does not detect the LOM alarm and does not change the scrambling mode. The state persists.