NGN need and challenges

The technological advancements in telecommunication is forcing a trend towards unification of network and services, setting up a stage for the emergence of next generation network-NGN. NGN is essentially an IP based network that enables any category of customers to receive wide range of services such as voice, data and video over the same network. The service layer in NGN is independent of underlying network and access is enabled across a wide range of broadband technologies, both wireless such as 3G, Wi-Fi, WiMax and wire line such as copper DSL, cable, fiber etc. A single IP network replaces the different transport networks. The migration to NGN reduces network and operational complexity resulting in better and reliable service. It offers unrestricted access by users to different service provider .It supports generalized mobility, which will consistent provision of services to users. In migration to NGN security is crucial. In IP based, which is convergent and has open environment, network infrastructure must be flexible and open towards various types of service. Although NGN offers almost ideal characteristics in mobile networking implementation of it have some serious problems to face. Lot of research is going on issues like vertical hand-off, automatic billing system also quality of system.