Abstract: A multi-services access platform is presented for supporting metallic test access in switching or multiplexing devices such as digital subscriber line access multiplexers (DSLAMs). The multi-services access platform includes a chassis within which a predetermined number of card slots are included. Each of the card slots includes a number of input/output ports. A backplane runs along the chassis and includes a metallic test access bus. The metallic test access bus is operable to selectively couple to one or more input/output ports within the line card slots of the chassis to establish one or more metallic test paths. A relay matrix may be used to provide the selective coupling for the metallic test access bus, and the flexibility provided by the configuration of the relay matrix supporting the metallic test access bus allows for a variety of different test access ports (TAPs) to be supported.