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               Comcast Turns Wi-Fi Gateways into Motion Detectors

   Adam Engst

   At Gizmodo, [1]Bruce Gil writes:

     [Comcast] announced this week that it is rolling out Xfinity Shield,
     a cyber and home protection platform available to millions of
     customers [with an Advanced Xfinity Gateway] nationwide at no extra
     cost. The service bundles cybersecurity and parental controls with
     WiFi Motion, a feature that can turn existing WiFi equipment into
     motion detectors.

     'An opt-in feature, WiFi Motion uses the WiFi signal from a
     customer's Xfinity Gateway to sense movement in their home ' no
     cameras needed or recordings captured,' the company wrote in a
     [2]press release.

     Comcast says that WiFi Motion works by detecting changes in the
     radio frequency signals traveling between routers and WiFi-connected
     devices.

   This piece turned into a rabbit hole. Much as Wi-Fi'based motion
   detection sounds like science fiction, it's not new. Home monitoring is
   the first use case suggested by the Wireless Broadband Alliance in its
   [3]introduction to Wi-Fi sensing, the umbrella term for using Wi-Fi
   signals in a radar-like fashion. Both that introduction and Comcast's
   materials about Xfinity Shield claim that Wi-Fi sensing offers more
   privacy than cameras or other sensors, which is probably true, but
   neither acknowledges that Wi-Fi sensing introduces its own privacy
   concerns and a certain creepiness factor.

   Although Comcast says that [4]WiFi Motion captures only motion activity
   and does not identify individuals, that's a choice, not an inherent
   technology limitation. Earlier this year, German researchers
   demonstrated that [5]Wi-Fi signals could identify specific individuals
   with 99.5% accuracy. Plus, since Comcast stores motion event data in
   its cloud systems, it's available to law enforcement and court orders.

   Realistically, Comcast's WiFi Motion feature probably isn't a huge
   privacy problem on its own. But I'm uneasy about the broader privacy
   question around Wi-Fi sensing. I don't have the background or expertise
   to evaluate the claims in [6]this blog post from Pascal Piron, but he
   says the 802.11bf working group analyzed the privacy concerns but
   failed to agree on what to do, so the standard shipped without any
   mitigation. (Comcast's feature [7]reportedly uses a proprietary
   technology from Cognitive Systems instead.) However, research suggests
   that [8]privacy is being taken seriously for 6G cellular, where similar
   issues crop up. With luck, the efforts in the 6G cellular world will
   bleed over to the Wi-Fi world before it becomes a problem.

   [9]Read original article

References

   1. https://gizmodo.com/millions-of-comcast-wifi-routers-can-now-tell-when-youre-moving-around-the-house-2000800324
   2. https://corporate.comcast.com/press/releases/comcast-introduces-intelligent-home-protection-a-new-category-for-the-connected-home-with-xfinity-shield
   3. https://wballiance.com/wi-fi-sensing-101-an-introduction/
   4. https://www.xfinity.com/hub/smart-home/wifi-motion
   5. https://gizmodo.com/researchers-issue-warning-about-tech-that-could-turn-every-router-into-a-potential-means-for-surveillance-2000763181
   6. https://pascalpiron.substack.com/p/wifi-sensing-and-the-privacy-fix
   7. https://wifinowglobal.com/news-and-blog/comcast-relaunches-xfinity-shield-with-wi-fi-motion-sensing-security-parental-controls/
   8. https://www.etsi.org/deliver/etsi_gr/ISC/001_099/004/01.01.01_60/gr_ISC004v010101p.pdf
   9. https://gizmodo.com/millions-of-comcast-wifi-routers-can-now-tell-when-youre-moving-around-the-house-2000800324

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