as is normal for such an outlet in this case a modem 83 being a power line carrier plc modem interfaces the hub 11 to the integrated data service splitter combiner unit 82 to allow data communication over the power line similarly in the case of a catv application where the catv wiring is used for the network infrastructure modem 83 is a coaxial cable modem and unit 82 isolates the catv signal from the data signal although the invention has been so far described as relating to ethernet ip based data networks the invention can be similarly applied to any type of data network furthermore although packet networks are the most common for local area networks the invention is not restricted to packet networks only and can be applied to any digital data network where network entities are identified uniquely by addresses furthermore although the invention has been described as relating to networks based on continuous electrical conducting media telephone catv or electrical power and the relevant modem and associated circuitry are connected in parallel to the wiring infrastructure the invention can be applied equally to the case wherein the wiring is not continuous but is in discrete segments.