Aspects of the present disclosure provide a technical solution that enables various passive optical network (PON) type infrastructures to coexist with dense wavelength division multiplexing (DWDM) network infrastructures. According to an embodiment, an optical communication network framework uses an optical coexistence topology to enable coexistence of PON type components and DWDM components. An optical coexistence system uses an optical coexistor to convey an upstream optical signal to one of an arrayed wave grating (AWG) of a DWDM system and an optical line terminal (OLT) of a PON by conveying unfiltered portions of the upstream optical signal to the OLT and filtered portions of the upstream optical signal to the AWG.