A user is authenticated to a defined space, by entering identification data and phone data that respectively identify the user and the user's phone to a server, by sending an application from the server along a wireless connection to the user's phone after entry of the identification data and the phone data by executing the application received by the user's phone to create a virtual symbol of virtual characters in the user's phone, by posting a security symbol in the defined space, by capturing a security image of security characters from the security symbol with the user's phone, by comparing the security characters with the virtual characters, and by authenticating the user to the defined space when the virtual characters match the security characters.