A system and method for optimizing the transmission of signals over a group of wires. In a preferred form of the present invention, a multi-wire bus connects a common card to a plurality of line cards. A framing protocol controls transmissions between the common card and the plurality of line cards. The framing protocol includes a frame having a prefix that identifies in which direction a given transmission will occur. The prefix also identifies over which wire or wires a given line card will receive data. Each of the line cards are configured to interpret the prefix so that at any given time data can be transmitted from the common card to one or more of the line cards by either transmission over a single wire or a plurality of wires.