The invention relates to a jack connector assembly having circuitry components integrated providing power over LAN-functionality, in particular for use with regard to Ethernet-networks. An object of the present invention is to provide a jack connector assembly providing integrated power over LAN-functionality and especially avoiding any undesirable and destructive heat accumulation. The object is achieved by a modular jack connector assembly having at least one connector housing (100) and at least one connector insert (200) insertable into the connector housing, each connector housing (100) having a front mating side with at least one port opening (301, 312) for receiving a plug having a plurality of electrical contacts and a rear side (112) for inserting at least one of said connector inserts (200), each connector insert (200) having a front end side and a rear end side and is supporting electrical contacts (240) with contact sections (245, 246) arranged at the front end for detachable connection with corresponding electrical contacts of at least one of said plugs, and is supporting at the rear end side components (260) of a circuitry providing a power over LAN-functionality.