Hi there!
This time, I will share with you a case about an alternative for the OLP protection path.
Problem Description
The customer wants to deploy a WDM OLP but they don't have a resource protection path.

Solution
Here is the alternative:

We can use the existing link to be a protection route, with a condition the existing route cannot bear the list of OCH Site A - Site B.
Prerequisite:
The OCH Site A - Site B and the OCH Site C - Site D must be different, to allow the OCH Site A - Site B flow to the link Site C - Site D.
A black and white that the customer are agree for the network configuration, is highly recommended.
Amplifier is needed to amplify the signal.
Procedure:
Deploy the network as diagram above.
Create the OCH trail at WSS Site A as a Source to the WSS Site B as a Sink with bidirectional.
When the link fiber Site A - Site B broken or fiber cut, the OLP will switch to the Site C and/or Site D:

That's all, I welcome everyone to leave a message and exchange in the comment area!
Thank you!


