All-optical switching is the future direction of development, but also from the current development trend, this "future" is not far away. Many in the industry view: ROADM-based networking and scheduling is not sensitive to the rate applicable to ultra-high-speed optical networking and scheduling transmission systems, but also can greatly reduce power consumption and floor room. After years of gradual improvement technology, functionality and performance, CDC-F ROADM (ie colorless and directionless without conflict and supports flexible grid capacity reconfigurable optical forked Multiplexer) device has matured, basically solved the light layer networking encountered many problems. Some foreign operators in the deployment of 100G networks have begun to do large particles using ROADM traffic scheduling, a direct transition to an all-optical network. March 2015, Verizon announced the adoption of Ciena and Cisco's packet optical transport platform Metro 100G deployment, CDC-F ROADM technology for the first time to get a commercial scale. In the same month, Alcatel-Lucent announced that Verizon will use its latest CDC-F ROADM technology to upgrade Verizon's long-haul optical transport network.

The main advantage of OTN is fully backward compatible, it can build on existing SONET / SDH management functions on the basis of not only the existence of a fully transparent communication protocol, but also for WDM-end connectivity and networking capabilities, It provides a light layer interconnect specification ROADM, and added sub-wavelength aggregation and grooming.