Jayateertha (Telecom Technology & Management Consultant, Bangalore, India) G. M. 
Convergence Through All-IP Networks [PDF ebook] 

The convergence of two powerful technologies-wireless and the Internet-through IPv4/v6 protocol has led to emergence of next-generation networks (NGNs). NGN is no more a network of mere computers but a connected conglomeration of varied networks with diverse physical properties, with a plethora of network elements, along with a variety of real-time