3. Some common resources for various applications ('generic application components') are: Content converters E-commerce servers Business logic The conclusion is that the word 'service' should preferably not be used on its own. The latest meaning of the word 'service' is: 'A service is a contractually defined behaviour that can be implemented and provided by any component, based solely on the contract'. This definition applies to web services and service-oriented programming, a future trend. Having talked about services the next step is to discuss networks. This term will be defined (for the book) at the beginning of the network-oriented chapter (Chapter 3). 3G and next generation networks (NGN) are specific network solutions. The book objective Clients Application control, e.g. browser Content Service Server Other resources User interface Common Application Business resources (SW components) Firewall logic Application interface Terminal located Service capability 2 Service enablers Service capability 1 Service enablers The network domain (UMTS, GSM, PSTN/ISDN etc) Figure 1.13 An overall picture of an application and its relation to a service offered by the application and its support functions Understanding Changing Telecommunications - Building a Successful Telecom Business to be general and holistic favours other expressions such as 'all-access networks' and 'horizontal networks'. Therefore 3G and NGN are not used very much. Another common term is 'broadband'. How broad is broadband? Originally (ITU-T recommendation I.113) it was faster than primary rate ISDN (in Europe about 2 Mbit/s, in the USA about 1.5 Mbit/s). Nowadays network operators advertise broadband at 256 kbit/s and higher. FCC in the USA has chosen 200 kbit/s since this bit rate is considered sufficient for full-motion video and changing web pages as fast as one can flip through the pages of a book. The term 'enabler' may also cause interpretation problems. In this book it is used with a meaning close to 'new standards'. In the literature sometime