The IP multimedia subsystem (IMS) is a major enabler for application delivery on top of all-IP infrastructures. However, it does not define end-user services or ways to create them; rather, it is comparable to a toolbox or an operating system. So operators have in the absolute an unlimited range of possibilities to develop service strategies based on IMS. Those strategies will be impacted not only by IMS but also by associated architecture components like service delivery platforms (SDPs) and end-user device architectures.

Major telecoms operators are committed to IMS implementation, so in the future we expect IMS to play an important role in operators’ service strategies in all-IP environments. However, developing new end-user services is not yet the main driver for large IMS implementations. Large IMS projects are driven by fixed telecoms operators wishing to migrate their legacy circuit-switched telephony networks to next-generation network (NGN) architectures. In the mobile domain, there is no such NGN programme yet and IMS implementation is driven by the introduction of a few new services, primarily in the field of interpersonal communication services like video sharing or push-to-talk.

To better understand the future role of IMS, it is necessary to consider how telecoms operators’ service delivery models may evolve.

Table of contents

Key messages

IMS-based applications: from vision to reality

IMS is an enabler for application delivery on top of all-IP infrastructures
Growing operators’ commitment to IMS
The IMS ‘vision’ faces important challenges
New business models for IP applications delivery

Telecoms operators’ business models in all-IP service environments
Operator’s role in the open-platform model
Service example: ‘network-enhanced’ portable game decks
Table of figures

Figure 1 IMS-enabled application delivery architecture

Figure 2 High-level architecture for IMS on the end-user device side

Figure 3 Role of the active phonebook

Figure 4 IMS infrastructure contracts (publicly announced only)

Figure 5 Operator announcements of IMS-based services

Figure 6 IMS vision versus real-life challenges

Figure 7 Three different business models for IMS-based applications

Figure 8 Scenarios for end-to-end delivery of IMS-based applications

Figure 9 Value chain roles for the different business models