Toward next-generation scalable, high-capacity, and programmable MBoSDM optical networks [Invited]

The continuous growth of data traffic and emerging 6G services will drive the evolution of current optical transport networks to support higher capacity and enhance scalability and programmability. Key innovative technologies, including multiband over spatial division multiplexing (MBoSDM) and software-defined optical networking (SDN), will enable the efficient increase of spectral and spatial resources and support dynamic and automated network operation. Hence, advanced transmission and switching solutions should be investigated that are capable of fully exploiting these technologies toward enabling dynamic, adaptive, and high-capacity future optical networks. In this paper, a next-generation MBoSDM scenario including an MB(oSDM) sliceable bandwidth/bit-rate variable transceiver (S-BVT) and an MBoSDM node prototype is experimentally validated in the ADRENALINE testbed and integrated within an SDN control plane considering different network use cases. Full programmability of the integrated solution is achieved through dedicated SDN agents and a unified SDN controller, demonstrating the provisioning of MB flex-grid and SDM connections. The proposed transmission and switching approaches significantly enhance network capacity, flexibility, and reconfigurability, offering a scalable pathway for future 6G optical transport infrastructures.