Multi-Granular Switching Node and Enabling Devices

Multi-band and space-division-multiplexing (SDM) is essential for realizing future high-capacity networks. A multi-band system needs to employ more bands other than conventional C+L bands, and SDM technology includes a multi-fiber system with multi-degree nodes. One challenge to realize multi-degree nodes is the scalability of devices. To address this issue, we propose a configuration of a multi-granular switching node by introducing a band cross-connect in addition to the conventional wavelength cross-connect, which relaxes the requirements for the devices. However, at the same time, new classes of devices need to be developed to construct the multi-granular switching node. We describe the multi-granular switching node and its enabling devices. We also prove that the proposed configuration of the band-granular switching node provides better transmission characteristics than a conventional CDC-ROADM only node.