IMS (IP Multimedia Subsystem) & NGN (next-generation networks)

A new buzz in the telecoms world is about the global migration to IP-based network popularly called next-generation networks (NGNs) and IMS (IP Multimedia Subsystem) is one of the few carrier-friendly models because it looks to blend Internet applications with a converged world of wireless and wireline facilities.
It uses a Voice-over-IP (VoIP) implementation, based on the 3rd Generation Partnership Project (3GPP) standardized implementation of session control protocol (SIP) which enables it to be multi-vendor in nature and will let carriers more easily and cost-effectively add applications via new application servers, thereby reusing the horizontal IMS framework for each application and not having to set up the session control layers over and over again. As it runs over the standard Internet Protocol (IP) and supports existing wireline and wireless networks. Basically IMS uses three protocols;
SS7 ( SS7 is fully embedded in the world’s telecom networks as a signaling protocol)
Sigtran (Sigtran is a suite of protocols that puts SS7 signaling onto IP transport)
SIP (an application-layer control (signaling) protocol for creating, modifying, and terminating sessions with one or more participants)
All this is being done to deliver and develop new, multimedia services quickly and cost-effectively. Confused-- OK, let me make it simple, all this is being done for you to have a Mobile Videophone on which besides making a Video call, you can play games online, watch movies, basically you will have full Internet access. Cool, isn't it??