Comment by transpute
3 years ago
Technical defenses are either cat & mouse CSI electronic warfare or shielding the walls+floor+roof+windows of some rooms (e.g. research labs in business, industrial systems, WFH offices, bedrooms) with materials like aluminum radiant barrier, RF window film or expensive drywall (e.g. QuietRock) designed for RF shielding of SCIFs.
Another defense, impractical for most people, is for their house/office to be physically protected by a tall fence that is far enough away from the building to exceed radio range, along with sensors at the fence to detect someone attempting to broadcast into the property. This could be combined with shielding to reduce the necessary fence-building gap.
Regulatory responses: some countries could restrict this technology to high-frequency 60Ghz mmWave which doesn't easily pass through walls. That would at least reduce the social issue of X-ray vision (via 2.4Ghz WiFi) through the exterior walls of existing homes and businesses.
One of the 802.11bf papers proposed an opt-out mechanism where human biometrics could be registered into a giant database and you could ask WiFi devices to unsee some humans. Good luck with that.
Another regulatory response could be to delay approval of Wi-Fi 7 and shipment of Wi-Fi Sensing devices until the WiFi industry pays to upgrade all existing houses with RF shielding, i.e. never. Maybe it would be sufficient to wait until the homes of celebrities and politicians were RF shielded? Let's not forget IP-sensitive and financial business offices with people typing on keyboards. And using combination locks. And...
I wonder how much shielding is actually needed. 2.4 GHz = 12.5 cm wave. A conductive grid with approximately 6cm (or 2") step should prevent the waves from getting inside. Not a very expensive thing to add even to drywall panels. Can also be relatively easily added into fabrics, to make RF-reflective curtains.