🤖 AI Summary
This work addresses the challenge of maintaining both multi-user fairness and real-time interactivity in 5G video conferencing under wireless resource constraints, which otherwise leads to significant degradation in Quality of Experience (QoE). The paper proposes the first substream-level QoE-aware architecture for 5G, featuring a closed-loop design composed of monitoring, control, and marking modules that dynamically adjust substream priorities. By synergistically integrating selective packet dropping and probe-based rate control, the framework jointly optimizes application and network behaviors. It achieves, for the first time in a 5G system, substream-granularity QoE-aware scheduling by incorporating key techniques such as deep packet inspection and RAN state awareness. Real-world experiments on a 5G testbed demonstrate up to a 70% QoE improvement over native 5G and state-of-the-art approaches, or alternatively, a 2× increase in background throughput at comparable QoE levels.
📝 Abstract
Video conferencing over 5G is increasingly prevalent, yet its Quality of Experience (QoE) often degrades under limited radio resources. This has two causes: 5G networks must serve many users, while interactive traffic requires careful handling. Motivated by the insight that different subflows within an interactive session have a disproportionate effect on QoE, we present the design and implementation of StreamGuard, a practical 5G architecture for subflow-level, QoE-aware prioritization. StreamGuard forms a closed control loop with three components: (1) a monitor in the Radio Access Network (RAN) that uses deep packet inspection to infer QoE and RAN state, (2) a controller that selects prioritization actions to balance QoE and fairness, and (3) a marking module that applies these decisions by marking packets to steer subflows into appropriate priority queues. StreamGuard further shapes application behaviors via mechanisms including selective subflow dropping and probe-based rate control, to align application behavior with radio constraints. Implemented in a real 5G testbed, StreamGuard achieves a superior QoE-fairness tradeoff compared to vanilla 5G and prior state-of-the-art approaches, improving QoE by up to 70% at comparable background throughput or preserving up to 2x higher background throughput at similar QoE.