Okay I'm as concerned about privasy as everybody else is here but i also gotta admire that its pretty neat they can actually do that. Are they measuring the signal echo like what radar does? If they controlled both the receiver and transmitter i wouldn't be as surprised to find out they can tell when something crosses between them and form a 2-dimensional mesh (like that episode of Star Trek TNG where geordie detects cloaked romulan ships by having starfleet deploy a fleet of ships that send signals back and forth and look for timing variances) but if I'm understanding correctly this is different because they only control a single point in the network?

I wonder if they have enough information to make out shapes or if it's just a simple rangefinder?

About fivish years ago I interviewed with a Wi-Fi device maker and the engineer I interviewed with was bragging that they could watch users walk around their home.

This is a neat feature when it's your own device that you control, but not so great when they "disclose information generated by WiFi Motion to third parties without further notice to you."

I wanted to talk about how responsible WiFi router software authors can make things local-only (and I've done that in the past; no way to get this information even if I wanted it). But this is always temporary when "they" can push an update to your router at any time. One day the software is trustworthy, they next day it's not, via intentional removal of privacy features or by virtue of a dumb bug that you probably should have written a unit test for. Comcast is getting attention for saying they're doing this, but anyone who pushes firmware updates to your WiFi router can do this tomorrow if they feel like it. A strong argument in favor of "maybe I'll just run NixOS on an Orange Pi as my router", because at least you get the final say in what code runs.

Put your cable modem in bridge mode and use your own WiFi.

I used to recommend using your own cable modem as well, but these days you have to use the Xfinity modem to avoid overages if you're in a market with data caps.

Comcast has a stellar network operations unit, but their business operations are creepy and exploitative.

Next step it will just be a feature they offer and whether you know of it, use it, or want it, it'll always be on in the background due to you signing a terms of service that lets them. And then it'll not just be in a xfinity router but your tv, phone, etc. Just makes me want to live in a cabin in the woods.

This is actually a feature of the Plume wifi mesh devices. https://support.plume.com/s/article/Sense-Live-View?language... It's also available from any other ISP that uses them, or if you buy your own Plume device and a subscription. It's been there for years. https://arstechnica.com/gadgets/2020/03/from-wi-fi-to-spy-fi...

  - Activity Tracking: Detects movement patterns to identify changes in daily routines to spot health concerns 
  - Sleep Monitoring: Tracks sleep duration, wake times and nighttime interruptions to assess sleep quality
  - Anomaly Detection: Establishes household baseline to proactively identify unusual patterns & changes in activity

Is Xfinity licensing Wifi Motion™ from Cognitive Systems?[0]

"WiFi Motion, Cognitive’s Wi-Fi Sensing solution, is an innovative software platform that leverages AI and sophisticated algorithms to transform existing Wi-Fi signals into a motion sensing network."

Another company operating in this space is Origin Wireless. They demonstrated breathing detection with WiFi in 2017[1]. They've since partnered with ISPs to offer a WiFi Sensing "TruShield" home security service.[2]

[0]https://www.cognitivesystems.com/

[1]https://www.engadget.com/2017-10-09-origin-wireless-motion-d...

[2]https://www.originwirelessai.com/trushield/

This reminds of an MIT-licensed library that was Vibe-coded and released three weeks ago. The source is available here: https://github.com/ruvnet/wifi-densepose

One more reason not to use an ISP router, although in this case most of us are at minimum carrying around GPS homing beacons in our pocket so the carriers already know where we are.

The term for this sort of thing is "WiFi sensing". Relevant HN thread from 2021 ("The next big Wi-Fi standard is for sensing, not communication (2021)"): https://news.ycombinator.com/item?id=29901587

As far as I can tell, devices were already on the market when that thread was made. 802.11bf was standardization to help along interoperability and future products.