Patent attributes
A method of multi-factor authentication is performed by an access control device. In response to detecting a beacon signal transmitted by a user equipment (UE) via a short-range radio access technology (RAT) the access control device sends a query to a location server for a current location of the UE. The access control device then determines whether the UE is within a threshold distance of the access control device and, if so, begins monitoring a signal strength of one or more beacon signals transmitted by the UE. If the signal strength of the one or more beacon signals exceeds a signal strength threshold, then the access control device may generate an access signal to indicate that a user associated with the UE is authorized to access a protected resource.