How many ways can you be spied upon? Far more than most of us realize. Our online travels are tracked by our ISP, by Google, by Facebook, and other large advertisers. Apple knows who we are and what we do. Now there’s a looming danger that Wi-Fi can be used to spy on us.
Yes, that Wi-Fi; radio waves that bounce around all over the place, but can also be used to identify specific objects. John Biggs on through-wall crowd counting via Wi-Fi:
The system, created by researchers at UC Santa Barbara, uses a single Wi-Fi router outside of the room to measure attenuation and signal drops.
Those occur as people walk through Wi-Fi signals. The gritty details:
The transmitter sends a wireless signal whose received signal strength (RSSI) is measured by the receiver. Using only such received signal power measurements, the receiver estimates how many people are inside the room — an estimate that closely matches the actual number. It is noteworthy that the researchers do not do any prior measurements or calibration in the area of interest; their approach has only a very short calibration phase that need not be done in the same area.
In simpler terms, the system can view people in a room based upon attenuation and signal strength, and, in preliminary tests with off-the-shelf technology, accurate to within a couple of people in a room of up to 20.
All objects in a room, people or otherwise, absorb Wi-Fi signals. People move, objects do not. Anybody else see the future lining up here? Now, let’s extrapolate this down the road a few years. How crazy does it sound now that the right hackers with the right equipment could also determine who is in a room (every human may have a different signature).
Researchers already can use audio capture technology to determine objects within a room in a similar manner. Sound waves go out, they bounce around, then bounce back to receiving microphones, and an application makes calculations based upon the bounced sound and identifies objects in a room.
If that sounds a bit like science fiction sonar, then you’re on the right track. What do you think of an always on Amazon Echo or Google Home talking speaker now? Maybe talking speaker isn’t the right phrase to use.
I’m thinking of always on and always listening and always learning about you as something that does not seem to be to my benefit as much as it is to Amazon and Google.