Xfinity routers can now sense movement in your home, without cameras

Comcast, the largest residential internet service provider in the US, is introducing a new feature called “WiFi Motion” that enables physical motion detection using nothing but Wi-Fi signals. By monitoring signal interference, WiFi Motion can accurately detect and track people and objects in and through physical space.

The technology behind WiFi Motion is still relatively new—we reported on Wi-Fi body fingerprinting last year—and has thus far mostly been theory and proofs of concept. Now, the theory is being put into practice.

In the Xfinity app, users will be able to enable or disable the “Xfinity Shield” option, according to Comcast’s official announcement. All connected routers and other network devices can then use WiFi Motion together to monitor the home and protect against intruders.

The service is free for Comcast customers and doesn’t require any additional cameras or sensors. However, the disadvantage compared to conventional home surveillance systems is that WiFi Motion doesn’t provide a clear image of the environment. Users can’t take photos or record videos, so in the event of a break-in, it’s not possible to identify faces or other visual characteristics.

Nevertheless, Wi-Fi-based surveillance is becoming increasingly attractive, especially among businesses. Alongside Comcast, other companies like Linksy, Wiz, and Philips Hue have also launched similar services. However, the technology still needs time to develop in order to become more accurate and less prone to errors.

Of course, there are privacy concerns, too. TechCrunch, for example, warns against using WiFi Motion in one’s own home without due care. In its terms and conditions, Comcast reserves the right to pass on data to third parties without informing users beforehand. This data could, for example, be used by governments for legal proceedings and more.