A bumper system for vehicles includes a tubular beam having front, top, bottom, and rear walls, and further having open tubular ends. The ring network includes a number of network elements, each including first and second switch fabrics. Hoses coupled at one end to diluent inlets to associated ones of the dispensing valves each have a connector at their opposite end which is adapted to be selectively and releasably connected with either the first or second orifice of an associated pair of orifices in accordance with whichever diluent is to be delivered by the hose to its associated dispensing valve. If the number of accesses for any of the rows during a first sub-frame exceeds a first threshold throttling accesses to the accessed row at a first rate.