Abstract: A method of obtaining tariff rates on a plurality of candidate service providers accessible to a roaming mobile subscriber for use in choosing the most suitable candidate service provider in a visited area. The method includes initiating registration by the mobile subscriber to a first candidate service provider. A request for subscriber's profile information is made by the first candidate service provider to the subscriber's home service provider. Additionally, the first candidate service provider sends the intended tariff rate to be charged to the subscriber to the home provider. The home provider determines which other candidate providers are accessible by the subscriber and requests tariff information regarding these providers. The home provider may then determine the most suitable provider based on the received tariff information e.g. the lowest tariff.

Abstract: A method of acquiring potential tariff charges assessed by wireless service providers to a mobile subscriber prior to registration is disclosed herein. The method includes transmitting a request for tariff information by the mobile terminal over a control channel to a candidate service provider. The candidate service provider determines an applicable tariff charge based on various factors such as roaming status, compulsory fees etc. The ensuing tariff charge is then transmitted back to the mobile terminal via the control channel. Subsequent tariff inquiries are made to other potential candidate service providers accessible by the mobile terminal. Once tariff information from all candidate service providers has been received, the mobile terminal may initiate registration e.g. with the cheapest service provider. The tariff information is able to be obtained prior to registering with a service provider, thus costs associated with registration are eliminated.

Abstract: An automated prepayment method for accessing wireless telecommunication services by a mobile terminal is disclosed. The method includes programming and storing in the mobile terminal subscriber credit information such as credit or debit card number, authorization PIN code, and the amount of prepayment credit to be bought. A registration request is sent containing a prepayment request indicator to the mobile switching center. The mobile switching center then requests that the mobile terminal transmit the programmed credit information. The credit information is sent to a prepayment clearing house to verify that the subscriber credit is satisfactory. If the response from the clearing house is positive then the mobile switching center grants the mobile terminal access to the network through standard registration procedures. On the other hand, if the subscriber's credit is not satisfactory then access to the network is denied and a corresponding message is displayed on the mobile terminal.