On the Scalability of WebRTC with Information-Centric Networking

WebRTC is increasingly adopted by real-time streaming applications beyond traditional multiparty collaboration, in virtue of its low-latency capabilities. To support large scale deployments, the WebRTC architecture has evolved from the original peer-to-peer design to a centralized MCU-based (Multipoint Control Unit) system first, then to a lighter, SFU-based (Selective Forwarding Unit) system where media encoding/decoding and rate selection is delegated to the clients. In this paper we present ICN-RTC, a real time communication architecture build on the latest SFU-based proposal that exploits the scalability benefits provided by Information-Centric Networking (ICN). We also propose the ICN-RTC synchronization protocol, a protocol that allows to use the pull-based transport of ICN without introducing additional latency to media distribution. We implemented ICN-RTC using Hybrid ICN, an incrementally deployable ICN implementation using IP. Preliminary results are encouraging: ICN-RTC scales with the number of active speakers rather than the total number of users in the conference. This allows for calls with ten times more participants with respect to the standard WebRTC, reducing the resources needed for the call by more than a hundred times.