Concurrent Multipath Transmissions for Live Concurrent Multipath
Transcription
Concurrent Multipath Transmissions for Live Concurrent Multipath
Institute of Computer Science Department of Distributed Systems Prof. Dr.-Ing. P. Tran-Gia Concurrent Multipath Transmissions for Live Video Streaming Thomas Zinner, Simon Oechsner, Tobias Hossfeld, Osama Abboud, Oliver Hohlfeld, Kurt Tutschku, Yuval Shavitt Tanja Zseby and Phuoc Tran Shavitt, Tran-Gia Gia [email protected] Motivation – Video Streaming Access Network Concurrent Core Network Multipath p Transmission CDN Access Network moderate high QoE Adaptation QoE QoE using H.264/SVC Thomas Zinner 2 Agenda Agenda QoE for Video Streaming Edge-Based Edge Based Quality Adaptation H.264 SVC Impact p of QoS on QoE Concurrent Multipath Transmission Mechanism Current Work within SJRP Multi-Next Conclusion and Further Work Thomas Zinner 3 QOE FOR VIDEO STREAMING Thomas Zinner 4 Edge – Based QoE Management QoE degradation due to insufficient available bandwidth: empty buffers and stalling (TCP) packet loss and artifacts / stream starvation (UDP/RDP) Negative, uncontrollable impact on user perceived quality (QoE) Bandwidth saving feasible by reducing: resolution frame rate image quality Negative, but controllable impact on QoE Enabler: H.264 SVC (cf. P2P SVC Demo) Thomas Zinner 5 Comparison of Bandwidth and Packet Loss Lower impact on QoE degradation due to controlled quality reduction Additional bandwidth usable for error correction Thomas Zinner 6 CONCURRENT MULTIPATH TRANSMISSIONS Thomas Zinner 7 Mechanism Base Layer re-sequencing i ? scheduling ? different path delays out-of-order arrivals Enhancement Layer But: packets arrive out of order at the destination Re-sequencing R i necessary Buffer B ff dimensioning? di i i ? Influence on the end2end delay? Thomas Zinner 8 Experiments Input: Number of paths Scheduling delay Path delay distributions Path capacity Source Destination buffer delay Output: Re-sequencing Re sequencing buffer occupancy distribution Random delay generation w.r.t. the path delay distributions Thomas Zinner 9 Impact of Skewness Transmission over two concurrent paths Impact of different mean values, but significant influence of skewness k Lower skewness leads to lower buffer occupation Path delay distributions with high asymetry should be avoided Thomas Zinner 10 Multi-Next – Measuring Multipath Transmissions EuroNF funded SJRP: UniWue, UniVienna, Fraunhofer, Tel Aviv ETOMIC-Box / Dimes •Traffic generation •TCPdump C 1st path Wien ETOMIC-Box: •Traffic consumption p •TCPdump 2nd path Colbud Jerusalem Rennes pooled ressource 3nd path Passau Deflectors Detailed investigation of the System: One-way delay of each path Re-sequencing buffer occupancy E2E delay Validation of existing theoretical models with measurements Thomas Zinner 11 Conclusion Multipath transmissions can be used for resource pooling Higher available bandwidth Out-of-order arrivals Impact on the e2e delay Theoretical investigations show the complexity of an appropriate selection: Re-sequencing buffer dimensioning Impact p on e2e delay y currently y under investigation g Future work: Measurements and mathematical modeling of concurrent multipath transmissions Implementation of a video streaming prototype Thomas Zinner 12 Q&A [email protected] Thomas Zinner 13