Media-over-Multipath-QUIC for Realtime Video Applications

2026-08-11

AI Summary

Real-time video transmission over multipath networks suffers from inefficiency due to schedulers neglecting the semantic distinction between key frames and enhancement frames. This work proposes a semantic-aware multipath scheduling mechanism by extending the MoQT protocol, enabling edge relays to make path decisions based on media object metadata and declarative rules. For the first time, application-layer semantics are introduced into the transport layer in the form of rules, without requiring tight coupling with video-specific logic. Integrating QUIC multipath transport, labeled network paths, and a rule engine, the system reduces the P99.9 frame completion time from 384.7 ms to 114.1 ms in a Starlink/WiFi hybrid environment, decreases playback buffering by 61.5%, and uniquely meets the 150 ms interactive latency target.

Abstract

Multipath transports place a client's WiFi, cellular, and satellite networks under one connection, yet real-time video gains little from them. The scheduler that assigns packets to paths sees only bytes, so it cannot tell a keyframe that anchors a second of video from an enhancement frame whose loss costs one image. We show that the limiting factor is not a shortage of path diversity but the absence of a channel through which the application can name what the transport cannot see. Media over QUIC Transport (MoQT), already deployed on production CDNs, carries media as named Objects, and relays forward each Object's metadata without interpreting it. The knowledge the scheduler lacks therefore already flows through the subscriber's relay. We present MoMQ, a MoQT extension that turns this metadata into path decisions. Applications and relay operators install declarative rules at the edge relay that match Object metadata and express delivery preferences against labeled paths. The relay evaluates the rules mechanically, so it acts on video semantics while containing no video logic. On a live testbed spanning Starlink and WiFi, four rules cut P99.9 frame completion time from 384.7 ms under the best transport-only scheduler to 114.1 ms and reduce the required playback buffer by 61.5%. MoMQ is the only configuration that meets the 150 ms interactive latency target. Across relays in two countries and subscribers on two continents, the same rules apply unchanged and retain their advantage wherever the paths remain disjoint.

Problem

• Multipath transport
• real-time video
• frame semantics
• path scheduling
• latency optimization

Innovation

• Multipath QUIC
• Media over QUIC Transport
• Semantic-aware scheduling
• Declarative routing rules
• Real-time video latency