is primarily used for accessing a service network over the Internet and from dial-up accesses. User authentication and IP address assignment - in addition to the GSM/UMTS authen- tication procedures (USIM - core network), a service network authentication of the user should be considered. This authentication guarantees that the current possessor of the user equipment is allowed to access a service network. Policy and multicast servers. 9.11 EXAMPLES OF SERVICE IMPLEMENTATION 9.11.1 FEDERATED APPLICATIONS Federated applications are built upon cooperating local and distributed services across the Internet. See Figure 9.14. Let us exemplify, using listening to music via the mobile phone: Connect via the WAP gateway to the wireless Internet portal and select your favourite music site. Click on the tune you want to hear and the tune is streamed to the phone. Whilst listening, the mobile advertiser sends a message saying that you have the oppor- tunity to purchase the CD containing this song at a discount price if you respond within 10 minutes. Click on the 'buy' link and connect to the CD store's page. You buy the CD via the mobile e-pay secure m-commerce platform. Finally you request to have the payment sent to your mobile phone bill. The operator sends the payment transaction data to its partner bank/credit card agency, which clears the payment to the CD store. Understanding Changing Telecommunications - Building a Successful Telecom Business Other network (CPE, Terminal If any) Service network with servers server Applications Service enablers Network control and intelligence Access Core connectivity Connectivity User information flow Figure 9.14 Federated applications The user should not be aware of the products and processes involved in this complex series of transactions. But achieving this is not easy. This demonstrates the power of the service network concept where all applications share common resources and interwork smoothly with each other. 9.11.2 MORNING NEWS APPLICATION As another example, we take a typical