Converging Dynamical Networks with Applications to Peer-to-peer Video Streaming and Social Networks

Håkan Terelius, Guodong Shi, Ather Gattami, Karl H. JohanssonACCESS Linnaeus Center

Royal Institute of Technology, Stockholm

LCCC Workshop on Control of Computing Systems, Lund, 5-7 Dec 2011

Jim Dowling, Amir Payberah Swedish Institute of Computer Science, Stockholm

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Live streaming

Broadcasting technology

Collaborative P2P distribution

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Mathematical model

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Node dynamics4

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Convergence analysis

Proof idea

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Convergence time

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Numerical simulations

Live-streaming application

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Experimental evaluationPlayback continuity under flash crowd

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ExperimentsPlayback latency under catastrophic failure

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Related results for average consensus

Shi & J, 2011

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Conclusions

• A gradient overlay topology can improve P2P live-streaming• Necessary and sufficient condition for convergence to such a

topology for an algorithm based on random sampling• Corresponds to sufficiently high sampling rate

Future work• Improved convergence rate through neighbor sampling• Dynamic networks and utilities

H. Terelius, G. Shi, J. Dowling, A. Payberah, A. Gattami, K. H. Johansson, Converging an Overlay Network to a Gradient Topology, IEEE CDC, Orlando, 2011.

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Thank you for your attention!

Questions?

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Neighbor sampling

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Neighbor samplingA simulation example

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Neighbor samplingThe line graph

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Neighbor samplingCurrent research

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Coupon Collector’s Problem

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Coupon Collector’s Problem

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Coupon Collector’s Problem

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