any roles this might lead to a number of re-organizations in order to successively tailor the staffing to the new situation. There is also a volume relationship in order to be competitive and profitable. If the roles are over-established, the market share for new entrants will not be sufficient for profitability. Terminology The terminology within the area is not very clear. Common expressions are value chains, value webs, service provider, content provider, network provider, actors and roles. A value chain is needed to create the end-user services. When there is a lack of a clear consecutive chain (which is the case in the Internet service area), 'value chain' might be replaced by 'value web'. 'Service provider' is not a very precise term, but it is used a lot, also in User data Business relationship Business relationship FAB = Actor-user User segments Content interface, with providers fulfilment, Retailers Life stage dimension assurance and Value/attitude dimension billing Business relationship Services, QoS, Security neutral to Application SM = Service Service providers Applications providers management Service enablers NM = Network management neutral to Control FP = Fundamental technical plans Core connectivity Carriers Access Access Figure 4.15 A horizontal network gives horizontal roles Understanding Changing Telecommunications - Building a Successful Telecom Business Terminal Other network(s) (CPN, if any) Service network, if any Content Content Service network External MM networks Network control and intelligence PLMN/PSTN/ISDN Access Core connectivity User information flow The reference model - distributed model to show network segmentation and reference points Figure 4.16 Reference points enhancing actor separation and cooperation - the target network interfaces are preferable this publication. Adding a further word, for example Internet service provider, creates clarification. One actor, e.g. Telia Sonera in Sweden-Finland, can take on many roles. Network providers or network operators own and operate 