The invention is directed to a pluggable module and mounting socket for use in an optical network terminal (ONT). In particular, the mounting socket accepts a pluggable module comprising either a dual-section triplexer card or a single-section diplexer card, thereby allowing a vendor to selectively change the type of PON transport by simply changing the diplexer/triplexer pluggable module to support either diplexer or triplexer applications. The ability to configure the ONT by swapping out the pluggable diplexer/triplexer module eliminates the need for a manufacturer to maintain two different versions of the ONT, i.e., with or without video.