GSO-simulcast

• DOI: 10.1145/3544216.3544228
• Publication Date: 2022-08-11T22:58:16Z
• Authors: Xianshang Lin; Yunfei Ma; Junshao Zhang; Yao Cui; Jing Li; Shi Bai; Ziyue Zhang; Dennis Cai; Hongqiang Harry Liu; Ming Zhang
• Keywords: Videoconferencing

We present GSO-Simulcast, a new architecture designed for large-scale multi-party video-conferencing systems. GSO-Simulcast is currently deployed at full-scale in Alibaba's Dingtalk video conferencing that serves more than 500 million users. It marks fundamental shift from today's Simulcast, where media server locally decides how to switch and forward streams based on fragmented network view. Instead, globally orchestrates the publishing, subscribing, as well resolution bitrate of each participant using centralized controller aware all constraints meeting. The automatically modifies stream configurations meet participants' real-time changes updates. In doing so, achieves multiple goals: (1) reducing mismatch, (2) less path congestion, (3) automated policy management. With deployment we observed 35% reduction average stall, 50% voice 6% improvement framerate. describe principle, design, deployment, lessons learned.