An SDN-enabled multi-layer protection and restoration mechanism

摘要

Transport networks consist of multiple layers, technologies, and areas of deployment. For example, they combine electronic packet and wavelength circuit switching in a single turnkey solution. Conventional solutions have for the longest time segregated the network management and control schemes of these layers, creating silos of operations. This legacy limits flexibility and programmability of extant solutions. In this paper, we describe PROnet, its SDN orchestrator, and a demonstration of its reliability while supporting an advanced manufacturing application running in decentralized mode. PROnet is a two-layer Research and Education Network (REN) under deployed at and around the UT Dallas campus. Resources in the PROnet Ethernet-over-Wavelength Division Multiplexing (WDM) two-layer architecture are managed by a hierarchical SDN orchestrator, which provides two critical functions: 1) on-demand multi-layer path provisioning and 2) coordinated fault handling at both layers. With the first function, the orchestrator automatically provisions optical circuits to efficiently meet the Ethernet flow fault-tolerant requirement as dictated by the application. With the second function, the orchestrator coordinates response procedures at both layers to overcome a first network outage and prepare the network to handle a potential second outage. We refer to this latter function as Multi-layer Protection (implemented at the Ethernet layer) and Restoration (implemented at the WDM layer) mechanism.