Abstract: An access control method comprises providing a handheld mobile wireless device that includes a user key uniquely associated with a user, and a facility communication device that transmits a facility key uniquely associated with the facility. The mobile device receives the transmitted facility key and retransmits the received facility key and the user key to a remote premise control server, which authenticates the received keys. The server transmits an access control command if the keys authenticate. The server regularly updates the facilities key and transmits an updated facility key to the facilities communication device.