Overlay network based on WebRTC for interactive multimedia communications

Real-time interactive communications have become critical for business, e-commerce, e-government and education. Teleconferencing systems have been usually deployed using proprietary and expensive systems. Overlay networks are often used to support multi-point teleconferencing and provide services unavailable in the underlying physical networks. With the advent of WebRTC, real-time communication applications can be implemented directly in the browser without installing custom applications or additional plugins. This paper proposes an overlay network based on WebRTC oriented to interactive multimedia communications. The overlay is organized in four planes for data delivery, signaling, control and floor control. The data distribution relies on a clustered organization of WebRTC clients interconnected through a reflector mesh, where a reflector mixes the streams coming from a single cluster. The overlay also includes self-organization techniques, re-organizing the clusters when clients leave or join. The signaling plane uses the Session Initiation Protocol (SIP) for the negotiation and establishment of media sessions between clients and reflectors. Signaling is centralized in a rendezvous point which is also responsible for re-organizing the data plane. Finally, the floor control plane is responsible for limiting the number of streams in the overlay by sharing the data channels between clients. Ubiquity of the communication services and interoperability with other WebRTC applications are the main advantages of our proposal.