Hypermodal - Dynamic Media Synchronization and Coordination between WebRTC Browsers

This paper describes a Web based real-time collaboration system, Hypermodal, based on the concept of temporal linkage between resources. The system allows the users to construct, manipulate and exchange temporal linkages organized as synchronization trees. The temporal linkage is defined by RDF <sync> predicate based on a novel use of Media Fragments URI and permits on-the-fly tree updates while the resources in the tree are playing. We propose RDF <mirror> predicate and a new protocol to correlate and initialize distributed synchronization trees without requiring clock synchronization. Moreover, we develop a new REST API optimized for efficient tree updates and navigations based on super nodes. The preliminary test results on a prototype system show the approach is feasible and promising.