WiFi routers now tracking motion: Xfinity’s new feature sparks privacy concerns

When you’re between your WiFi devices, they can detect even small movements, such as a hand wave. It’s not future tech: Xfinity users can already use a router and other devices as motion sensors. The downside: the motion data is also collected and can be shared with third parties.

Since the start of the year, Xfinity, a major Comcast brand for telecommunication services in America, has been notifying users about a useful new feature, WiFi Motion. It allows turning internet devices into motion sensors that monitor movement at home.

At no extra cost, the Xfinity app allows users to select up to three WiFi-connected devices and will alert users if motion has been detected between them. Once set up, the printer, smart fridge, an Xbox, or any other IoT device will also turn into a motion sensor.

“With high sensitivity, you may detect small movements like the wave of a hand,” the support page states.

The new feature is tailored for enhanced home security and only requires a compatible leased gateway, such as an Advanced Xfinity Gateway (Technicolor XB7 model or later).

However, users in a recent Hacker News discussion expressed growing concerns over privacy implications.

Xfinity’s privacy policy states that the company collects motion activity and information if users have the feature turned on, as well as other data.

“Subject to applicable law, Comcast may disclose information generated by your WiFi Motion to third parties without further notice to you in connection with any law enforcement investigation or proceeding, any dispute to which Comcast is a party, or pursuant to a court order or subpoena,” the Xfinity support page also states.

How does it sense motion?

WiFi signals travel between the router and other devices, and anything between them can disrupt the signal. WiFi signals bounce around, and the sensing area is not a straight line but an oval between the two devices.

Motion between the gateway and a connected device will be detected even across rooms and floors. However, the system will not tell the exact location of the movement. When the movement is detected, the app alerts users via push notifications, telling them “which connected device sensed the activity.”

While this information is useful for the home, Xfinity specifies that it is not a security system and is not professionally monitored.

The users should ensure that the three devices have strong WiFi signals. They may also want to maximize coverage by placing the router in the central location of the home and spreading the three connected devices to cover a larger area. Xfinity recommends avoiding placing two devices directly above or below the gateway on another floor.

The app offers many options. By default, WiFi motion detects even small amounts of movement, including small pets. It cannot always distinguish large pets from small children. Users can adjust sensitivity. High sensitivity is recommended for most captures and when not sharing walls with neighbors.

“On the WiFi Motion settings page, you can enable or disable notifications or create schedules to receive notifications only during certain times of the day (e.g., you may only want to be notified of motion at night or times you are typically away from home),” Xfinity explains.

The WiFi motion feature will not work with mobile devices, such as phones or tablets, or devices connected through WiFi extenders.

Xfinity has been notifying users and publicly introducing the new tech since the start of the year.

Users concerned

While innovative and useful, the feature seems to be raising some concerns among users.

“Is WiFi quickly becoming a low-resolution camera with the ability to see through walls?” a concerned Reddit user asked five months ago after receiving a notification about the new feature.

This week, a new discussion on Hacker News popped up with tech pros discussing privacy implications, as the motion detection may allow ISPs to monitor household activity and potentially share this data.

“Sounds like, at least in some limited circumstances (using the provided WiFi AP, having this feature turned on, etc), ISPs are going to be able to tell law enforcement/courts whether anyone was home at a certain time or not,” the user jacobgkau posted.

However, others noted that even without the new feature, ISPs or authorities can still ascertain whether users are at home by analyzing internet traffic patterns. Mobile devices constantly ping various services even when not in use.

While some called for legal protections from ISPs “spying on their customers,” others suggested taking matters into their own hands. A VPN can help protect users' traffic from being tracked by their ISPs, and users should have complete control over their router.

“I've been telling people for ages not to trust ISP-provided hardware. Notice the vague language here, which means they reserve the right to share private information for anything that might be called an investigation, or for any dispute which includes them (didn't pay your bill?), or a subpoena,” another user said.

However, yet another user notes that “Xfinity won't give folks in certain locales (maybe everywhere in the US?) unlimited bandwidth unless they use their modem/router.”

Cybernews has reached out to Comcast for a comment and will include its response.