Orchestration Of Reliable Three-Layer Networks

In Wavelength Division Multiplexing (WDM) networks, even a single network element failure can cause significant traffic losses due to the disruption of many active data flows. Protection schemes are widely adopted to mitigate the adverse effect brought in by such devastating failures. Particularly challenging is the application of protection schemes to multi-layer networks. In multi-layer networks, upper layers' data flows and circuits depend on the availability of lower layers' circuits, thus creating strong interdependency. For example, when fulfilling constraints imposed by Shared-Risk Link Groups (SRLGs), the number of viable working and protection routing solutions is significantly restricted. In some cases, these routing restrictions may severely limit the overall network throughput and performance. In this study, the authors address this challenge in a three-layer network architecture and describe a time-efficient procedure that is suitable for implementation in multi-layer network orchestrators.