RESIDENTIAL · WI-FI SENSING · SHARED-WALL BOUNDARIES

Xfinity warns that WiFi Motion can report activity from neighboring units or shared walls.

Wi-Fi signal disruption → motion event → neighboring-unit activity can cross the sensing boundary → cloud history

Xfinity WiFi Motion is an opt-in feature that uses compatible Xfinity gateways, extenders and selected stationary Wi-Fi devices as a motion-sensing network. Comcast says movement is detected when it disrupts the wireless signals traveling between the Xfinity equipment and selected connected devices. It does not use a camera, capture images or video, record audio, or identify an individual.

The physical sensing boundary does not necessarily stop at the property line or apartment wall. Comcast recommends Medium sensitivity for duplexes and townhomes that share a wall and Low sensitivity for apartments or homes sharing multiple walls. Its troubleshooting documentation specifically lists frequent alerts from neighboring units or shared walls as a symptom of excessive detection.

Comcast says motion-event history is stored in its cloud systems for seven days so the customer can review activity in the Xfinity app. Its support documentation also states that information generated by WiFi Motion may be disclosed in response to valid legal process such as a subpoena, court order or search warrant.

Why it matters: The person whose movement affects a sensing system does not necessarily have to own the sensor, connect to the network or know that the feature exists. In shared-wall housing, movement outside one household can potentially create a motion event inside another household's Wi-Fi sensing system.

Primary sources: Xfinity Support — Using WiFi Motion · Xfinity — WiFi Motion FAQs · Xfinity — WiFi Motion overview and retention

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