Identifying an unknown subscriber identity module (SIM) includes reading a first value representing a mobile directory number from the SIM, where the first value is automatically read prior to a registration of a mobile device with a network, and reading a second value representing the mobile directory number from the SIM, where the second value is automatically read after the registration has occurred. The method includes evaluating the first and the second values representing the mobile directory number, and determining a provisioning status associated with the SIM based on the evaluating.