Telecommunications service providers are facing challenges with little or no growth in core markets and nimble competitors attacking profitable niches. In coming up with the Next Generation Network, Telecommunication services providers have identified the need for new profitable services and to reduce the cost of existing ones. The desire to upgrade the current network and to embrace the new technology will allow them to move into a new telecommunication technological frontier. In their quest for solutions, service providers have realized that the Next-Generation Networks can help them to address a myriad to these challenges. Inherent in the IMS NGN Architecture is the separation of call control, switch fabric, and application programs, tied together over a Quality of Services enabled IP Network. This architecture offers fast service creation over a Flexible infrastructure. By supporting new services, the IP Multimedia subsystem (IMS)next generation network can help service providers to build stronger customer relationships.