Network Network service cost Resource costs reservation Entrance fee (installation, and use Periodical operations) subscription Figure 5.17 Elements in a subscriber charge - forces affecting the charge Services for advertisers, and possibly usage/content fees measured in for example Mbytes for applications.) The imminent forms of traffic transfer (access, 'find and connect', network service) charging can be based on the following parameters: Volume - the amount of data transferred, measured in for example Mbytes. Duration - for example the duration of a session over the packet path in GPRS (a packet data protocol (PDP) context session), or duration of voice, video conference or video telephony calls. Time - date, time of the day, day of the week. Final destination - the destination address, such as an address in a specific network. Location - the location of the subscriber. Perhaps different charging in 'home zones' and 'office zones' and 'hot spots'. QoS - the defined QoS classes (conversational, streaming, interactive and background) may be replaced by something more precise, which can be based on priority in the net- work. Reverse charging - the sending party or a third party pays. Free of charge Flat rate - a fixed monthly fee. Prepaid will be used also in the new telecom world. Probably prepaid and flat rate will dominate during the next few years. For prepaid the operator can check the account in real time, to make sure that the money is available, before the end user can use a service. For UMTS operators the access fees may contain: Airtime fees, as a function of transferred Mbytes, QoS level and traffic class. Monthly subscription fees. QoS level per traffic class. Connection fees. Obviously QoS level and traffic class are getting much more into focus. In the long run usage/traffic volume may disappear (compare TV) as subscribers might leave the operator. The service content/application part could be charged by the access operator or the service provider/content provider. See Figures 5.18 and 5.19. For IP