In conjunction with a wiring in a house carrying data network signal, a modular outlet (100) includes a base module (100a) and interface module (100b). The base module connects to the wiring and is attached to the surface of a building. The interface module provides a data unit connection. The interface module is mechanically attached to the base module and electrically connected thereto. The wiring may also carry basic service signal such as telephone, electrical power and cable television (CATV). In such a case, the outlet provides the relevant connectivity either as part of the base module or as part of the interface module. Both proprietary and industry standard interfaces can be used to interconnect the module. Furthermore, a standard computer expansion card (such as PCI, PCMCIA and alike) may be used as interface module.