The content can be coded in different ways, such as AMR, MPEG-4, XML and VML. The receiver must be able to decode the received standard. The small presentation format of mobile terminals must be considered. Security and QoS protocols might be necessary (tunnels, RTP, RTSP, RTCP). Header compression protocols are an advantage, especially for IP calls. New signalling protocols may be required in the terminal (SIP, SDP, possibly H.323 type of protocols.) Configuration over the air is important, as well as device management. Network capabilities It should be possible to select capabilities in the network that correspond to the desired application demands regarding quality and security. Advanced (IN type) FP control functions are necessary in voice/multimedia type networks. Solution in brief In order to handle client and server-specific features, a functional block is allocated in the client-server interface to the network layer. This block must be able to adapt between fairly unpredictable user needs, interpreted by the application developers, and the network(s). It has another important task, namely as location for various application logics and their associated developer-facing service enablers and a service delivery platform architecture. A corresponding service management function is found on the management side. The service delivery platform or framework contains middleware functionality that can support multiple applications in the mobile devices. Examples of platform functions are network access and device mapping, and device management including configuration over the air. A good relationship with a systems integrator is valuable. Some key enablers are the application programming interface (API), which is explained below, and service enablers. New sets of applications are designed by means of new service enablers. See Chapters 8 and 9. In order to be flexible in responding to user needs without changing existing devices, flexibility by means of Java (or similar) enabled devices is critical. This represents pr