Xfinity WiFi Motion is an opt-in piece of WiFi Shield. It does not add a camera or a puck. It watches for movement as a change in the WiFi signal between a leased Xfinity gateway and a few devices that stay on and stay put. When something crosses one of those paths, the Xfinity app can send a push notification and keep seven days of events. Notifications name the connected device that sensed the disruption, not a room and not a person. Setup is on Xfinity's support page: https://www.xfinity.com/support/articles/wifi-motion

The house needs Xfinity Internet, a compatible leased gateway (Technicolor XB7, XB8, XB9, XB10, MXB1, or XER10), the Xfinity app, and stationary devices that do not sleep. The feature is off until someone turns it on from the Home tab and accepts the residential agreement. Alerts can be split across Home Watch, Away Watch, and Dark Watch. For WiFi Shield, Dark Watch stays quiet unless WiFi Motion alerts are enabled for overnight.

This fails for Storm-Ready WiFi, a CommScope XB7, bridge mode, Pro Protection, Xfinity Home Security, or a Pro WiFi Extender. It also fails in weak-signal rooms, on Ethernet-only gear, on phones that leave the table, or when the oval between the gateway and the TV misses the hallway that matters. Comcast does not monitor the alerts and does not warrant detection. Pets around 40 pounds and small children can look the same to a radio wave.

Get it if the leased gateway is already eligible and the goal is awareness, not a face on a clip. Skip it if the box is excluded, the house is on Xfinity Home Security, or a camera is the actual requirement. Install is the app toggle plus a walk-through test of the rooms that should ping.

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