Referring to FIG.  1, a diagram of a conventional traveling-wave switch 50 is shown.  A gate voltage (i.e., Vg) is applied to a gate through a resistor Rg.  When the gate voltage Vg is low, the switch 50 is considered closed.  While closed, the switch 50 passes a current (i.e., ID) through a drain between two ports.  While the gate voltage Vg is high, the switch 50 is considered open.  While open, the current ID is routed from the drain into a source as multiple currents (i.e., ISA-ISN).  The currents ISA-ISN induce a parasitic slot mode return current (i.e., IM).  The parasitic slot mode return current IM flows in an opposite direction of the current ID.  The parasitic slot mode return current IM degrades an insertion loss performance and an isolation performance of the switch 50. 
It would be desirable to implement a traveling-wave switch with multiple source nodes.