Unsuccessful 1: N Protection Subnet Search

Unsuccessful 1: N protection subnet search.

Product

OptiX BWS 1600G

Fault Type

Protection

Symptom

Use one OCP and two LWF boards to form the OTU 1:N protection. After the physical fiber is connected, the protection group is configured on the two stations, respectively. But search of the WDM protection subnet on the T2000 always fails.

Cause Analysis

On the T2000, the search of WDM protection subnetwork is based on the WDM path, and the WDM path on the T2000 is based on the fiber connection on the T2000. Therefore, after the physical fiber connection is completed, the fiber connection between the OCP and OTU should be created on the T2000. After that, search the WDM path. Then, search of WDM SNCP according to the WDM path will be successful.

Procedure

1. First create the fiber connection between the OCP and LWF on the T2000, and then search the WDM path. It is found that search of the WDM path fails.
2. After an inspection, it is found that the transmit frequency and the receive frequency of the protection LWF board are different. Under this situation, though the service can be available, path search on the WDM side will fail.
3. Replace the LWF board at the opposite end to ensure the transmit frequency and the receive frequency is consistent. Search the WDM path again. At this stage, the search of the WDM path and SNCP is successful.

Reference Information

• The transmit frequency and receive frequency of the OTU board that used for OCP protection must be consistent.
• Fiber connection between the OCP and OTU should be created on the T2000.
• Search the WDM path before searching the SNCP.

More related:

What Caused Occasional NE Unreachability

How The SSE3LWF Board Reports the OTU_LOF Alarm When Interworking with the SSE1TMR

New- and Old-Model Boards on ASON Networks of WDM Products