Four OptiX OSN 3500 NEs form an MSP ring, as shown in Figure 1.
Table 1 shows fiber connection between the NEs.
|Local End||Opposite End|
|NE Name||Slot||Board Name||Port||NE Name||Slot||Board Name||Port|
During the MSP ring switching test, only NE-143 and NE-144 are successfully switched and switching for the other NEs fails.
Modify the MSP ring into an SNCP ring and then perform the SNCP switching. The switching is normal.
All the K1/K2 bytes received at the west board (7-SL16) on NE-144 are "0". As a result, NE-144 and the downstream NEs fail to receive the K1/K2 byte from the east board (12-SL16) on NE-143. Hence, it is determined that NE-143 and NE-144 may be faulty. Table 2 lists the received and transmitted K1/K2 bytes.
|Transmitted K1/K2 byte||0x0230||0xcd||0xd3||Transmitted K1/K2 byte||0x0320||0xdc||0xd3|
|Received K1/K2 byte||0x0000||0xff||0xff||Received K1/K2 byte||0x0230||0xfd||0xcf|
Refer to Table 1. It is found that NE-143 can receive the K1/K2 bytes from NE-144 normally. The received K1/K2 bytes, however, are always "0x0000" regardless of whether NE-143 transmits any K1/K2 bytes whose values are "0x0000". In addition, the KC and KM bytes are abnormal. NE-144 fails to receive the K1/K2 byte that is normally transmitted from NE-143. The K1/K2 bytes received in slot 7 on NE-144 are always "0x0000". In addition, it is found that WDM equipment is located between NE-143 and NE-144. Hence, it is suspected that the WDM equipment changes the K1/K2 byte from NE-143 to NE-144. At the same time, WDM equipment in other segments may also affect the K1/K2 bytes, especially the KC and KM bytes.