Wavelength service is modeled as a specialized logical connection using the ClientCircuit entity. Wavelength service is carried over several other logical and physical entities. A failure in any one or more of these entities will cause the wavelength service to be down.

A failure or fault event in any object underlying the wavelength service is propagated through all layers up to the wavelength service, the ClientCircuit entity. The ServiceUnavailable event will show the underlying fault or failure as the root cause of the problem.

Wavelength service, the ClientCircuit, typically rides over one or more ClientTrails. While the ClientCircuit represents user’s end-to-end connection, the ClientTrail is used for internal logical connections within the network.

As shown in Classes and relationships in wavelength service, underlying the ClientTrail is the OcnLink. An OcnLink is layered over OchLinks connecting multiplexers and demultiplexers. OchLinks are layered over one or more FiberLinks which represent the lowest physical layer.

Figure 1. Classes and relationships in wavelength service