Overview of IP Multimedia Subsystem Protocols and Communication Services

Background

The convergence of fixed and mobile networks has made it possible to use new technologies for end-users and for operators and vendors. The evolution of fixed and mobile technologies results in cost-effective advanced access technologies (Harrowell, 2006). The IP Multimedia Subsystem (IMS) architecture is a universal communication platform. Its architecture offers many voice, video, and multimedia services as well as end-user applications.

The IMS architecture provides multimedia services based on Internet technologies and SIP protocol (Burger, 2006; SIP, 2008). SIP is the main signaling protocol for the IMS architecture and, using SIP, any IMS terminal can communicate with any SIP-based Internet terminal (3GPP Overview). The 3GPP Release specifications define the IMS architecture with mobility and differentiated QoS services (Hwang, 2008).

Many services are based on IMS, such as:

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  Multimedia Messaging Service (MMS),

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  Push-to-Talk,

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  Instant Messaging,

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  Presence Service,

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  Location Services.

The successful collaboration of Open Mobile Alliance (OMA) (OMA Overview), European Telecommunications Standards Institute (ETSI), and Technical Committee within ETSI, which works on standards for Next Generation Networks (TISPAN), has made it possible to use these advanced communication techniques.

According to collaborative joint working, the core network becomes the entity that decides suitable QoS for a certain media stream associated with a service request (3GPP TS 23.107). IMS sessions allow differentiated telecommunication services to be used and they allow IMS operators to make IMS services adapted to the market, with customized QoS services and customized specialized functions (3GPP TS 23.107).