ABSTRACT
The use of SIP signaling messages can create a huge number of real-time networked multimedia services. The call services show some preliminary examples of how multimedia-rich intelligence services can be created. The creation of RT multimedia service is a limitless opportunity whose true potential needs to be explored with deep inventive insights. We only describe a few SIP call services, including call transfer, call diversion, referring calls to multiple resources, call services with content indirection, third-party transcoding call services, INFO method with mid-call information transfer and INFO Packages, call control user-to-user information services, call services using dual-tone multifrequency, and emergency call services. Each of these basic call services can offer/create a host of many other rich multimedia call services extending the basic call service. The detail of each basic call service and its extensions are explained along with call flow examples.
