Software defined synergistic IP+optical resilient transport networks [Invited]

Integrated orchestration of the IP+optical transport network has been well studied in recent years and has become a realistic trend in telecommunication network deployments. OpenFlow-based software defined network architecture is among the emerging and intensively investigated unified control plane solutions. Numerous previous works have focused on enabling optical networks to support the OpenFlow control plane, but mostly discussed from the single controller's point of view. In real operational scenarios, however, there may inevitably exist different operators in different network layers/domains, and it is too idealized to have only one controller that is responsible for all devices. In light of this, here we propose and demonstrate an enhanced control plane architecture with hierarchically fabricated OpenFlow controllers. We specify the interworking relationships between different controllers on both IP and optical layers, and by using an IP+optical cross-layer information model, we show the effectiveness of unified routing and scheduling in terms of reducing the service blocking rate. Finally, dynamic cross-layer traffic adjustment and restoration are also successfully demonstrated on our implemented synergistic IP +optical network testbed with coordinated controllers.