ing Changing Telecommunications - Building a Successful Telecom Business Man-machine interface audio, video, graphics Application control Service layer communication Possibly (applications) a device service enablers connected (mobility support) SIP etc by means of bluetooth or IR Access Single, dual, mobile, fixed, triple mode Possibly a device using Terminal function, includes signalling the terminal Attach, detach = Network access control as a router access interfaces Not to be forgotten: Things that communicate Figure 10.2 Main terminal functions and interfaces Terminals connect at the lower layers to a public or private network by means of a terminal-network interface. There is a vast range of terminals from simple telephones to complex enterprise net- works. The service explosion makes service and application downloads a crucial issue to achieve flexibility. There is a trend from simple terminals (such as fixed telephones) and an 'intelligent' network, towards 'intelligent' terminals/terminal clusters and a variety of networks with varying capabilities depending on the traffic types. Examples of intelligent terminals are computers and the new mobile terminals, both of which use the whole TCP/IP protocol stack. Terminals with cameras or video cameras are already here. There is an increasing need to build home networks. The service enabler Bluetooth may play an important role in facilitating such development. Terminals can act as network relaying elements connecting to other terminals, for example when connecting laptops to mobile terminals or in what is called ad hoc networks. Another strong trend is towards 'things' (washing machines, coffee machines, engines) that communicate. In addition to 'classical' customer premises equipment, such as tele- phones, faxes, PCs, etc., many microelectronic controlled devices (stereo/video products, home theatre, white goods, light control, burglar alarms, person identification/location systems, etc.) are used in a household. Most of these systems are currently stand-alone