Choir: Tackling RTBC Performance Impossible Triangle with 5G Collaboration

2026-05-04

AI Summary

This work addresses the longstanding challenge in real-time broadband communication where achieving high throughput, low tail latency, and multi-user fairness simultaneously—a so-called “impossible triangle”—remains elusive. The paper proposes Choir, a novel coordinated rate control scheme deployed at 5G base stations that uniquely integrates physical-layer resource allocation and dynamic latency characteristics into sender-side decisions. By co-designing wireless-aware scheduling with video traffic modeling, Choir enables architecture-level synergy between network infrastructure and application demands. Experimental evaluations across diverse 5G scenarios demonstrate that Choir substantially improves average throughput, reduces tail latency, and ensures inter-flow fairness, thereby effectively overcoming the aforementioned performance trade-offs.

Abstract

Real-time broadband communication (RTBC) scenarios, such as cloud virtual reality and 8K live streaming, further raise the criteria of the performance triangle, requiring video bitrates exceeding 30 Mbps, tail delay below 50 ms, and fairness guarantees for multi-user concurrent access. Based on our testing and analysis, existing RTBC-oriented rate control solutions, including end-to-end algorithms and network-assisted algorithms, fail to simultaneously satisfy all performance metrics. The native dynamic delay and physical-layer resource allocation strategy inherent to the 5G radio access network (RAN) are the key reasons. These solutions lack adaptation to the 5G architecture, leading to reduced decision performance. This paper proposes Choir, an innovative collaborative solution mainly deployed on 5G base stations that deeply integrates 5G radio characteristics and video streaming traffic patterns to guide efficient sender-side rate control. Extensive simulation and testbed evaluations demonstrate Choir's significant performance in achieving high average bitrate, low tail delay, and inter-flow fairness across different 5G network scenarios.

Problem

• real-time broadband communication
• performance triangle
• 5G RAN
• rate control
• multi-user fairness

Innovation

• 5G RAN
• real-time broadband communication
• rate control
• collaborative optimization
• QoS fairness