An apparatus and method for shortening propagation delays of a plurality of repeater circuits that are interconnected to form a single repeater. A tree structure that organizes the plurality of repeater circuit so that an activity signal from one repeater circuit is propagated to other repeater circuits via a multi-branching network wherein a downstream repeater circuit is connected to at least two upstream repeater circuits. Any particular repeater circuit notifies the other repeater circuits, via an expansion bus, of a collision whenever two or more upstream indicator signals are asserted, or when at least one upstream indicator signal is asserted and the particular repeater circuit has one port active, or when the particular repeater circuit has multiple ports active. Each repeater circuit asserts an indicator signal to a downstream repeater circuit whenever one of its upstream indicator signals are active or one of its ports is active. An alternate embodiment provides for selective control of the repeater circuits via a mode control that permits tree operation or uses an external arbiter.