A passive entry adapter system includes an external band rejection filter connected to an external network; an entry adapter connected to the external band rejection filter, an input port connecting the entry adapter to the external network; a directional coupler connected to the input port; a frequency-based signal separation device connected to a first terminal and comprising a high-pass terminal, and a low-pass terminal; a splitter connected to the high-pass terminal, where the splitter is configured to be connected to one or more first types of devices; and a broadband output port connected to a second terminal of the directional coupler. The broadband output is configured to be connected to one or more second types of devices. The entry adapter and the external band rejection filter are configured to prevent signals from a frequency band associated with in-network communications produced within an internal network from reaching the external network.