The 3GPP IP Multimedia Subsystem (IMS) has been designed to enable the deployment of value-added multimedia services in a secure and multi-vendor interoperable environment. Mobile and fixed network operators and service providers can use this common platform to enhance the service offering with innovative features such as Presence, Push-to-Talk-over Cellular, VoIP, Enhanced Gaming, Video Sharing, etc.

The IMS Framework from fg microtec (fgIMS) provides a layered architecture to ease the development, integration and porting of multimedia applications requiring IMS features. A System Adaptation Layer includes the necessary interfaces to the target platform and OS. An IMS Service Layer provides the IMS features and functionalities that enable multimedia application development. On top of these layers, the handset manufacturer can develop their own applications or choose one fg's exciting IMS based applications.

This architectural concept allows the IMS services to be agnostic of the target platform for easy development and fast porting. Moreover, the fgIMS Framework enables the handset manufacturer to integrate its own applications through well defined APIs. Alternatively fg microtec offers a complete integration and porting package including own IMS Applications and Graphical User Interface (GUI).

fg microtec's commitment to the development of interoperable products based on open standards is reflected in the IMS Framework. fgIMS contains a complete feature set of multimedia protocols and functionalities ranging from signalling and transport protocols to authentication algorithms, media and content handling, session control and QoS mechanisms. These elements are fully compliant with the 3GPP IMS, ITU-T and IETF specifications. fg microtec has accumulated extensive experience in IMS inter operability testing with major infrastructure IMS vendors and participates regularly in OMA (Open Mobile Alliance) and GCF test events to ensure multivendor interworking for IMS.

The fgIMS framwework is designed to allow multiple and concurrent access to IMS features, irregardless whether the applications requiring these IMS services are provided by fg or a 3rd party. The Adaptation Layer supports the necessary target and OS specific Adapters like sockets, timers, memory, etc. The Service Layer is composed of Service Blocks (SBs), which are modular entities providing the IMS required functionality such as Registration, Authentication, Session Management, Media Control, etc.

On top of this architecture, the IMS Framework supports the easy integration of multimedia applications by using Application Blocks (ABs). fgIMS can be ported to practically any platform and OS, including feature phones, smartphones and pocket PCs.

• IMS registration
• IMS authentication
• IMS privacy
• IMS addressing
• Session management (SIP/SDP)
• Signalling compression (SigComp)
• Real-time transport (RTP/RTCP)
• Transport Layer Security (TLS)
• Nat transversal mechanisms (STUN, NAT keep alive)
• Presence (SIMPLE)
• Group List Management (XCAP)
• Multiple codec support (e.g. G.711, AMR, GSM FR, H.264, MPEG-4)
• QoS for jitter- and delay-sensitive applications
• Forward Error Correction (FEC) and Unequal Level Protection (ULP)v