N-TSVS: a videoconference tool for generic cooperative groups

The paper presents the architecture and the design of a distributed videoconferencing application called N-TSVS. The structure of the cooperative groups supported by N-TSVS is defined and modelled by graphs: their vertices describe the group members and their edges represent the information sharing between the cooperative agents. The group dynamicity is modelled by valid configurations that are subgroups of members in which data exchanges can occur. A group membership service and an associated protocol that manage the dynamic cooperative groups are formally designed, validated and integrated inside N-TSVS. The multimedia data processing is developed in a separate way using multithreading functionalities and is coupled to the group membership service