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
zinner@informatik.uni-wuerzburg.de
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
 zinner@informatik.uni-wuerzburg.de
Thomas Zinner
13