Optical Networking Best Practices Handbook

12.2. FLOW-THROUGH PROVISIONING AT ELEMENT MANAGEMENT LAYER

Flow-through provisioning at the EML (which is the focus of this chapter) faces the following challenges:

• Optical network element resource reservation

• Sharing of optical network element resources across multiple network management systems (NMSs)

• Commit mechanism of reserved optical network element resources

• Rollback mechanism of reserved optical network element resources [1]

12.2.1. Resource Reservation

The EML maintains different pools of resources. These pools are the allocated resource pool, unallocated resource pool, and reserved resource pool. The NML sends a request for allocation of resources to the EML. The nature of this request is for the EML to reserve unallocated resources, but not make the resource operational, as the provisioning operation is yet to be completed. The EML identifies the resources from the unallocated pool. These resources are verified with the corresponding optical network element for its availability [1].

Upon confirmation of availability from the optical network element, the EMS moves these resources from the unallocated pool to a reserved pool. A unique reservation code is generated by the EMS and sent to the NMS in the response message. This reservation code can be used by NMS in the future for commit or rollback provisioning [1].

12.2.2. Resource Sharing with Multiple NMS

In certain network management configurations, a single EMS needs to serve more than one NMS. In such scenarios, there ...