Call party handling using the connection view state approach: a foundation for intelligent control of multiparty calls

A number of emerging broadband services require the ability to manage multiple parties and/or media. For instance, broadband videoconferencing bridges together more than two parties. A telemedicine service could enable doctors to converse over bidirectional video and audio connections, and share X-rays and patient data over unidirectional data connections. To manage the complexity of multiple parties and media, a rigorous model of the connectivity of a call is essential. Furthermore, an application-level protocol is needed so that a broadband service may request changes to the connectivity. A promising object-oriented model and protocol is at the heart of the connection view state approach. This approach was created to enable call party handling, which may be defined as "intelligent network control of stable calls with two or more parties". The ITU-T has standardized this approach for narrowband calls. Extensions to the connection view state approach have been proposed to support broadband services.