Chinese
English
OSN3500 SNCP (Sub-Network Connection Protection) Sub-Network Connection Protection is mainly used to realize the protection of cross-subnet services with double transmitter-receiver selection. The subnet can be a chain, a ring or a more complex network. With the function of double transmit and receive, it is applicable to the protection of cross-subnet services. When using the single-site method to configure SDH services, when the services across the subnet need to be protected, they can be realized by creating SNCP. The biggest feature of the service is that it adopts a dedicated physical channel as the protection channel, and the service is dual transmitter-receiver selective. When configuring SNCP services, you need to configure the working service and the protection service separately. The network is configured with SNCP to be able to protect the SNCP service on the working path. When SNCP over MSP is used, the SNCP over MSP protection inversion fails due to the problem of setting the protection inversion condition of SNCP. This problem can be solved by setting the HP_UNEQ alarm as the SNCP inversion trigger condition.
OptiX OSN 3500 II
OptiX OSN 3500 II
OptiX OSN 3500
Fault Category
- Protection Reversal Fault
- HP_UNEQ
Phenomenon Description
NE1, NE2, NE3, NE4, and NE5 form an MSP ring with an STM-1 link between NE1 and NE3. An SNCP VC-4 service is created between NE1 and NE3. This VC-4 service has a working source on the MSP working path and a protection source on the STM-1 link. the SNCP delay time is 100 ms. when the first fiber break occurs (between NE1 and NE2), the MSP inversion is normal. When the second fiber break occurs in the MSP ring (between NE3 and NE4), the SNCP service is interrupted and no SNCP protection inversion occurs.
Cause analysis
When the second fiber break occurs, check the SNCP inversion status. the SNCP inversion status of NE1 is normal, which is the reason that no SCNP inversion occurs. In this VC-4 link, NE1 reports the HP_UNEQ alarm to the main control board and the network management. Analyze the cross-connections on NE4 and find that no cross-connections are created. On NE5, the MSP protection paths are all traversed. It can be concluded that the NE4 protection is not crossed causing the problem. all VC-4 signals are null and the HP_UNEQ alarm is reported on the downstream network element.
Procedure
- Set the HP_UNEQ alarm as the SNCP inversion trigger condition. Test again and the inversion is successful.
Reference Information
None.
The technical information in this chapter and the related SDH equipment troubleshooting process are provided by Shenzhen Optical Transmission Network Technology Co.(www.opticaltrans.com), please retain the reprint. Huawei SDH optical transmission equipment, SDH transmission equipment sales phone: 13430988088 Welcome to call!
