Even a faraday cage would be insufficient if I can get a powermeter into a power outlet on the same circuit. Or if we're talking about a datacenter, I just need

Even a faraday cage would be insufficient if I can get a powermeter into a power outlet on the same circuit. Or if we're talking about a datacenter, I just need a good electrical measurement device (Voltage, Amperage, Frequency, PF) on the cable outside. I can, in this example, just have the computer use more power to signal a 1 and less power to signal a 0. For a DC I just ramp up the entire DC load. Do that over the span of a week or so to make it less noticable.