IP multimedia subsystem and its protocols: A step to convergence

Today´s world has been changing drastically over few past years in aspect of telecommunication technology development. World has become a small village, connected via large variety of media and devices. With grow of telecommunication industry popularity a need of Internet-mobile-fixed convergence has grown to be a significant issue to be considered and implemented. The matter is important as combining latest trends in technology will result in maximalizing user experience. The intention of this article is to present IMS and its protocols possibility to provide efficient technology convergence. Different aspects of this unification are being considered. Not only is the IMS a key to network convergence but service and device convergence as well. A role of SIP and short over view of other protocols is also present in the paper.