The data from a channel can be dropped to the node or new data can be added to the node using Re-configurable Optic Add Drop Mux (ROADM) that uses Wavelength Selective Switching (WSS) to extract and infuse a configured frequency. This eliminates the need to convert all the channels to electric signals, extract the required channels, and convert the rest back to optical into the OTN. Thus ROADM systems are fast, less expensive and can be configured to access any channel in the OTN pipe.