nications - Building a Successful Telecom Business Services, today Services in next generation network structure Services Transport Access transport & switching networks Users Figure 3.17 The layering will take time in the control layer because of the existing signalling systems Applications IP multimedia subsystem (IMS) domain server server server server PS domain mobile Control f. server Router SGSN MGW functions GGSN MGW Corporate functions Internet Router Multiservices IP network hot spot GSM/GPRS/EDGE UTRAN GERAN Figure 3.18 Example of the new horizontal 'all-access' architecture tend to speak about the main layered functions such as communication control, ser- vices and applications rather than nodes in PSTN, GSM or the Internet. A node can be seen as an implementation option of functionality location, usually comprising more than one layer. Networks and Technologies Service network and IP infrastructure servers Applications Service/User management IP infrastructure Service Portals content AAA, notification etc DHCP, DNS etc enablers HSS/HLR Network support servers traffic Communication control Network management MSC/TSC server SGSN control f. CSCF/BGCF Billing/accounting GMSC server GGSN control f. MRFC/MGCF Customer care TeS server CS SIPServer IMS Connectivity network Packet backbone Corporate Internet WLAN hot spot GSM/GPRS/EDGE PSTN/ISDN GERAN Cable UTRAN fixed wireless access Figure 3.19 A server-rich target network where all new media industry-based applications can be distributed to many access networks/different users Layering and functional split can be achieved in many ways, usually based on some kind of layered architecture model (OSI, TCP/IP). The development is also a matter of convergence as described earlier in this chapter. Relationships between business, network design and management are further elaborated in Chapter 4. The architecture will be further explained in this chapter, with the con- cepts of network, convergence, layering, stratification and fundamental technical plans as pedagog