// VERIFICATION FACTOR 4 OF 7

📍 GPS Geofence

Your browser's GPS API provides a location check against your home anchor. The geofence is a circle of configurable radius (default 500m) around your enrolled coordinates. Must be within the fence for mail access.

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NOT CHECKED
Click Check GPS to request browser location
IMPORTANT — GPS LIMITATIONS
GPS can be spoofed. This factor is a supporting signal, not a primary defence. Link Star uses GPS alongside Starlink IP prefix AND the physical LoRa beacon heartbeat. An attacker would need to simultaneously spoof three independent location signals — which requires physical proximity anyway.
Indoor GPS. Browser GPS on desktop devices uses WiFi/IP geolocation, not true satellite GPS. Accuracy may be 100–500m. Phones with a clear sky view get 3–10m accuracy. Set your geofence radius accordingly.
GEOFENCE CONFIGURATION
⏳ Not yet checked
HOME LATITUDE REQUIRED
HOME LONGITUDE REQUIRED
GEOFENCE RADIUS (metres)
HOW TO FIND YOUR COORDINATES
1

Google Maps

Right-click your location on Google Maps → click the coordinates shown at the top of the menu. They copy automatically.

2

Click "Request GPS" above

If you allow location permission, your current coordinates will be filled in automatically and saved as the home anchor.

3

Set appropriate radius

500m is good for rural Devon. Urban areas with dense GPS interference may need 200m. If you frequently get false negatives, increase to 1000m.

SETUP LINKS
RESOURCEURLNOTES
Google Maps (find coords)maps.google.comRight-click → coordinates
What3Wordswhat3words.comPrecise 3m square location
OS Maps (Devon)osmaps.ordnancesurvey.co.ukOrdnance Survey detail
MDN Geolocation APIdeveloper.mozilla.orgBrowser API reference