Nowadays, many multimedia cluster-to-cluster applications exist, such as 3D tele-immersion (3DTI), computer-supported collaborative workspaces (CSCWs), distributed multimedia presentations (DMP).... All these applications have sophisticated data transport requirements due to the use of multiple, semantically related flows of information. A synchronization mechanism must be used to synchronize the playout of the streams, regardless of the number of receivers and the number of streams played on the receiver clusters. In this paper, we present a new solution for multimedia group synchronization in such applications. Rather than base the solution on the definition of a new synchronization protocol (as other authors do), we base it on small modifications or extensions to RTP/RTCP standard protocols already used in most multimedia applications. Due to this, the overload introduced by the approach is minimal. The suitability of the approach was evaluated in a real one-way cluster-to-cluster application, with satisfactory results.
