A Real-time Simulation Framework for Complex and Large-scale Optical Transport Networks based on the SDN Paradigm

Thanks to the recent advancements in the Software-Defined Networking (SDN) and Network Function Virtualization research domains, telecom operators are encouraged to upgrade their optical transport networks towards programmable, energy-efficient, service-oriented, and interoperable architectures. The availability of a large set of open-source building blocks, supported by different standardization bodies makes the selection and the integration of such technologies a very complex task. In this context, the INTENTO project has the objective to create an innovative simulation framework by selecting the best technologies and use it to test applications, services, and advanced optimization algorithms in a real environment. In the initial phase, the project designed a large-scale, distributed, and hierarchical Transport SDN architecture, where optical switches and networking functionalities are monitored and dynamically configured through a two-level structure of SDN controllers. On top of that, Virtual Network Functions are optimally deployed and managed by a centralized orchestrator, based on network condition, user requests, and application requirements. Based on this architecture, the project team started to develop a complex simulation environment that harmoniously integrates within the OpenStack cloud: optical node simulators composed by simulation agent and a suitable hardware emulation layer; proprietary SDN network controller designed to enable the innovative optical nodes characteristics; Open Network Operating System as the second level controller, enabling the integration of third-party or standardized models (multivendor environment), based on standardized interfaces and communication protocols. After having described the main components and functionalities already implemented into the simulation framework, the paper concludes by highlighting future research and development activities.