One embodiment relates to a method of providing dual-homing in a Layer 2 switch. In particular, the present invention provides for using a switch to transparently aggregate storage devices. They are simply slipped through holes in the frame for use. The subtraction module subtracts the first low pass filtered signals from the gain input signals to produce first stage signals. A vertically extending ground via is provided with the conductive pad being electrically connected to the horizontally ground plane conductors through the vertically extending ground via. The modified cells, whether in vivo or ex vivo, transgenic animals containing them, and food products obtained from those animals ) are also within the scope of the present invention.