IP Multimedia Subsystem


IMS functional architecture overview

IMS functional architecture overview

The IP multimedia subsystem (IMS) represents a uniform open architecture platform for a managed IP-based infrastructure that will enable the deployment of both basic calling services and an unlimited number of wireless-enhanced rich multimedia services that mix telecom and data services. In this context, rich means bundling multiple service enablers (e.g., voice/video connectivity, presence, instant messaging, conferencing, gaming, TV broadcasting).

By itself, IMS does not specify any new service. Instead, it provides flexible tools and a unified platform for network operators and service providers to build and create their access-agnostic service scenarios by means of reusable service enablers.

IMS research activity within the IP Technologies Area is called “IMS-capable Core Network for enabling Next Generation Network services” and focused on following research lines:

traffic load estimation towards IMS-capable core network from users of 3GPP and non-3GPP network (WLANs, WiMAX, etc.),

performance evaluation of IMS-capable core network nodes (e.g. GGSN),

working out of ways to create and orchestrate wireless-enhanced rich IP multimedia services by means of the IMS platform over heterogeneous access networks,

study of different IMS aspects related with an architecture to enable IMS-capable femtocell subsystem,

deployment of IMS prototype based on open source software to evaluate the performance of IMS-related components and different IMS/NGN services and integration of the prototype with the EXTREME testbed® to validate IMS operation in close-to-real environment.



  • Andrey Krendzel, 3G/4G Mobile Network Planning Aspects: IMS-capable Core Network Dimensioning and Radio Access Network Topological Design for Enabling NGN Services, VDM Verlag publishing house, October, 2008, ISBN 978-3-639-09011-6
  • Andrey Krendzel, Jawad Hussain, Josep Mangues-Bafalluy, Marc Portoles-Comeras, Framework for IMS Service Scenario Implementation, in Proceedings of the 2nd Open NGN and IMS Testbeds Workshop (ONIT-2010) in conjunction with TRIDENTCOM-2010, 18 May 2010, Berlin (Germany).