Session Initiation Protocol (SIP) is the foundation for most emerging communication services; it is transport layer independent and easily extensible. In fact, SIP-based applications can be deployed by all communications service providers from traditional Fixed Line and Mobile Operators to Internet Service Providers (ISPs).

SIP-based services range from required utilities to new revenue-generating applications such as Femtocell Gateways, Convergence Servers, IP Multimedia Subsystem (IMS) elements, softswitches, mobile-to-fixed gateways, Voice over IP (VoIP) elements, file sharing applications, voice or video conferencing, messaging, and gaming platforms.