In the past few years the mobile devices revolutionized to the extent that leveraged the end-users expectations to have a seamless cellular access to all-to-date Internet services. The IP Multimedia Subsystem is the key technology that makes it possible to access Internet services from emails and instant messaging to VoIP and Video transmission through the cellular network. In other words, IMS provides a seamless access to the Internet independent of the network type, either wireless or wired network, the terminal type, either mobile orfixed, the device, either PC, user equipment or even a TV.
IMS specifications were first introduced in 3GPP Release 5 as an enhancement to Packet Switched (PS) domain supporting IP Multimedia Services. IMS can be interpreted as the multimedia session and service control for PS domain. Besides, IMS provides inter-working functionalities to existing networks such as the traditional Circuit Switched (CS) domain, PSTN/ISDN networks and the Internet as well as the establishment of multimedia sessions in the same or between different IMS domains.
IMS provides the complete solution to support any IP multimedia application, including voice and video communications. It is a three-layered structure allowing full convergence in terms of access, services, charging, control, and management. The three-layered structure ensures that IMS is access-independent and thus different access networks can be used to deploy IMS achieving the convergence ever aimed for. In addition to the initially supported GPRS-CN access (Cellular), 3GPP has added WLAN in Release 6 (WiFi) and xDSL in Release 7 as additional IP-Connectivity Access Networks (IP-CANs).
IMS allows easy and fast service development and integration through the specification of common functions such as registration, authentication, authorization, security, charging, session management, policy and bearer control. IMS also offers an open application and service architecture, thereby allowing fast deployment and operator differentiation. In this context, IMS can be viewed as "the" application enabling platform of the 3GPP Core Network.
All these aspects -- including the use of well established common IETF protocols such as SIP and SDP -- are beneficial from an operator's, service provider's and manufacturer's perspective to enable the convergence of data, speech and mobile networks. Even organizations outside 3GPP can easily define services on top of IMS using its common functions. This concept was proven with the development of the Push-to-Talk over Cellular (PoC), SIMPLE Presence, XML Document Management (XDM) and Instant Messaging (IM) services by the Open Mobile Alliance (OMA).
This virtually provided operators and terminal manufacturers with infinite capabilities to develop myriad enriched services for their end-users through a cost-effective IP-based platform namely, the IMS. One of the key applications built on top of IMS and aiming for enriching end user experience is the Rich Communication Suite (RCS) group of standards. RCS is an initiative led by GSMA and a group of operators, terminal vendors, infrastructure providers and other telecommunication companies, gathering their efforts to standardize these desired services . RCS is a suite of applications and services defined by GSMA that enables interoperable, enriched communications and feature rich services including Enhanced Phonebook, Enhanced Messaging and Enriched Voice Calls. RCS covers a group of services including: presence, image share, SMS/MMS, Instant messaging, file transfer, and Video Share.
From a user equipment (UE) point of view, this requires a flexible IMS client framework equipped with several standardized service enablers so that the end user gains full access to this new and emerging world of mobile multimedia applications. IPneo capitalizes on these promising and standardized technologies to provide robust solutions that help operators and terminals manufacturers reshaping and enriching their end-users’ experience thus meeting their ever growing needs.
IP Multimedia Subsystem (IMS)