CONVERGE: QoE-driven Multipath Video Conferencing over WebRTC

Video conferencing has become a daily necessity, but protocols to support video conferencing have yet to keep pace despite the innovation in next-generation networks. As video resolutions increase and mobile applications using multiple cameras for photos and videos become popular, the need to meet the Quality of Experience (QoE) requirements is growing. Multipath protocols could be a possible solution. In this paper, we show that a straightforward extension of WebRTC for supporting multipath can perform worse than legacy WebRTC and propose CONVERGE, a WebRTC-compliant multipath video conferencing platform. CONVERGE improves QoE through three main components: a video-aware scheduler, video QoE feedback, and video-aware and path-specific packet protection. The video-aware scheduler uses the real-time video structure to schedule packets, and the video QoE feedback from the receiver helps the scheduler adjust the number of packets on each path. Additionally, the video-aware and path-specific packet protection mechanism improves on the existing FEC mechanism in WebRTC by considering the trade-off between FEC and QoE. CONVERGE is built as part of the Chromium browser, making it compatible with any device or network path. CONVERGE improves overall media throughput by 1.2x, reduces end-to-end latency by 20%, and enhances image quality by 55% compared to WebRTC.