What is API

The Next Generation Network (NGN) is a very complex environment, where various parties (network operators, services and application providers, integrators, etc.) necessarily cooperate on the provision of advanced converged services. This chapter presents the current status and fundamentals of conventional, converged and bundled valueadded services, and then depicts their transformation into distributed NGN services. The characteristics of NGN services are considered with respect to the architecture of the NGN service stratum and the enterprise framework, both standardized by the International Telecommunications Union (ITU). Finally, the implementation and deployment of interoperable NGN services through open interfaces are considered in conjunction with market trends and the standardization efforts of several international organizations or other independent initiatives, forums, alliances, etc.