The traditional constellation of networks shows a clear separation between the fixed network and the mobile network. Both networks have their own, firmly defined interfaces and transitions. With the convergence between cellular mobile networks and WiFi, it is possible to use all telecommunications services with a single terminal, regardless of the access technology used by wire or radio. Faultless switching between networks and services is controlled by service providers. This technology is implemented in Generic Access Networks( GAN).
The FMC approach, Fixed Mobile Convergence, which was developed by the European Telecommunications Standards Institute( ETSI), refers to network convergence and takes into account reachability at any location, whether stationary or mobile, under one telephone number. According to the FMC proposals, the subscriber has only one voice mailbox and receives only one bill. He has access to all types of information anywhere and at any time and can use the same services on the road as in the office or at home.
Fixed Mobile Convergence conceptually considers terminal mobility, service mobility and personal mobility. Terminal mobility allows the subscriber to take his personal terminal with him wherever he goes and to use it wherever he happens to be. Services mobility provides the telecommunications subscriber with a set of consistent services, regardless of the terminal device, access network, and location, and personal mobility ensures that the subscriber can be reached at a number wherever he or she is. The latter involves roaming between the different networks and providing the same consistent services across the different networks.
In contrast to network convergence, fixed mobile convergence (FMC), fixed mobile integration( FMI) focuses on service convergence and combines performance features of different Tk services of fixed and mobile networks. And Mobile to Mobile Convergence( MMC) is functionally equivalent to FMC, except that the transition from a cellular mobile network to a WiFi network is automatic, without a service provider.