Another way to prevent snooping is to prevent access to the signals. Many devices contain metal mesh shielding to absorb radio emissions [0]. For example, mic

Another way to prevent snooping is to prevent access to the signals. Many devices contain metal mesh shielding to absorb radio emissions [0]. For example, microwave ovens have a mesh window that passes visible light (~500 nm) but not microwave heating radiation (~100mm). How can one insulate a building against RF leakage? [0] https://en.wikipedia.org/wiki/Electromagnetic_shielding https://en.wikipedia.org/wiki/Electromagnetic_shielding