Cost-efficient Request Mapping for Large-scale Live Streaming Services.

The live streaming landscape has shifted to a crowd-sourced paradigm, resulting in highly volatile and geographically diverse viewer demand. To handle growing traffic, Content Delivery Networks (CDNs) increasingly rely on a mix of dedicated infrastructure and lower-cost, heterogeneous edge resources. Our analysis of production data reveals two emerging characteristics in modern live delivery: dynamic regional supply-demand imbalance and per-stream heterogeneity in popularity and geography. However, existing request mapping solutions fall short in this new landscape, as they assume stable regional capacity and overlook stream-level heterogeneity. This paper proposes LiveMap , a cost-efficient and latency-aware request mapping system for live CDNs. LiveMap performs online bandwidth provisioning via dual-level coordination to resolve regional supply-demand imbalances and reduce bandwidth costs. Further, LiveMap introduces an adaptive stream mapping strategy that dynamically forms per-stream delivery groups based on real-time popularity and system load. Deployed in Bilibili CDN serving crowdsourced live streaming over a year, LiveMap reduces bandwidth costs by 42.18% and access latency by 20.26%, outperforming the state-of-the-art solutions.