The present invention provides a method, apparatus and system for a protocol and line-rate transparent WDM passive optical network architecture that scales in terms of bandwidth and number of ONUs. Both an included optical line terminal and each of a plurality of ONUs use substantially the same reflective modulators to modulate respective wavelength channels to impart data thereto. In various embodiments of the present invention, the reflective modulators are composed of a SOA having on one facet a pigtailed fiber and the other facet coated with a highly reflective coating. In the WDM passive optical network of the present invention, the ONUs each comprises a separate wavelength for communication in the upstream and the downstream directions. The present invention allows for all-passive components to be placed in the field, thus, requiring no power between a central office and a user or subscriber's premises.