The telecommunications industry has seen a rapid boost within the last decade. New realities
and visions of functionalities in various telecommunications networks have brought forward the
concept of next-generation networks (NGNs). The competitions among operators for support-
ing various services, lowering of the cost of having mobile and cellular phones and smartphones,
increasing demand for general mobility, explosion of digital traffic, and advent of convergence
network technologies added more dynamism in the idea of NGNs. In fact, facilitating con-
vergence of networks and convergence of various types of services is a significant objective of
NGN
