ies regarding call control, which leads to a billing model not very attractive to many network operators. On the other hand smart billing requires a sophisticated call control, to clearly identify the different calls or sessions and to store the data associated with them for detailed billing. Integrated business chain with Flat rate connectivity billing, service extensive billing capabilities billing determined by service provider Telco's Differenciated & Service billing approa integrated billing Service Service provisioning provisioning Flat rate Flat rate for bit transport Connectivity Call control billing Connectivity Connectivity Traditional IP service service approach Figure 16.22 Typical billing principles in Telco and IP approaches Telecom Management - Operations As already said IP is now evolving towards an increasing use of call control, where the deployment of SIP may play a very important role. What will be the prevailing charging philosophy today remains an open question. The convergent environment may be particularly beneficial regarding billing and cus- tomer care processes. When all services are provided on one common platform it is easier to migrate customers from one service to another, both in terms of procedures and of phys- ical changes. It is no longer necessary to disconnect the customer from one network and reconnect her/him to another network. This is especially relevant to keep operational costs (OPEX) down, particularly when hands-on intervention is required on remote or no longer manned network elements. 16.7.2 DATA WAREHOUSING The term data warehousing means that lots of data are stored and post-processed to find many particulars about the subscribers and the network. As a strategic marketing advantage, modern marketing trends known as 'personalized marketing' or 'marketing one-to-one', collect information about customer activity on the network and use it to promote particular offers suiting end-user needs and personality. Examples are use of individual applications and their geographi