A CONFERENCING SYSTEM FOR REAL-TIME, MULTIPARTY, MULTIMEDIA SERVICES

In this paper, we describe a conferencing system designed to provide r eal-time, multiparty, fully interactive multimedia services. The requi rements of multimedia conferencing service can be summarized as follow s. First, there are a number of participants, and the number of partic ipants varies dynamically for service duration. So there must be a pro vision which allows members to join and leave a conference. Second, ea ch multimedia data has its own characteristics, and they have very clo se relationship to one another So, the Quality of Service(QoS) require ments of each media must be satisfied separately and at the same time their relationship must be maintained at the playback rime. For exampl e, the audio and video data must be synchronized at the playback time. Considering above requirements, we designed a multi-party, multimedia conferencing system. It is mainly composed of two control entities. g roup manager and media manager A group manager controls and maintains the participants group according to group attributes, and a media mana ger performs call admission control according to ifs anticipation of n etwork status at the call request time, and controls media data sendin g rate based on the receivers' periodic media reception quality report s. For more efficient control, we take into consideration the group ch aracteristics in the media control algorithm, Feasibility has been con firmed by laboratory trials.