Reciprocity with Virtual Nodes: Supporting Mobile Nodes in Peer-to- Peer Content Distribution

Transcription

1 Reciprocity with Virtual Nodes: Supporting Mobile Nodes in Peer-to- Peer Content Distribution CNSM/SETM Workshop , Zürich, Switzerland Dipl.-Wirtsch.-Inform. Matthias Wichtlhuber Tel PS Peer-to-Peer Systems Engineering Prof Dr. David Hausheer Dept. of Electrical Engineering and Information Technology TUD Technische Universität Darmstadt Rundeturmstr. 10, D Darmstadt, Germany Tel , Fax CNSM/SETM Workshop , Zürich, Switzerland author(s) of these slides 2012 including research results of the research network PS and TU Darmstadt otherwise as specified at the respective slide 0

2 Motivation Current IPTV and Mobile Trends [1] Athletics: Men s 100m final. 22% of overall traffic in the US. CNSM/SETM Workshop , Zürich, Switzerland 1

3 Motivation Incentive Schemes Mobile content distribution is use case of increasing relevance Video streaming Distribution of applications and system updates Peer-to-Peer (P2P) offers means for scalable content distribution by utilizing clients resources Incentive Schemes Rational (=selfish) peers need incentives to provide resources Reciprocity is commonly applied Discrimination of mobile peers Mobile peers can only reciprocate at high cost (energy/bandwidth/monetary) Uploading Penalty WiFi Uploading Penalty HSDPA Energy penalty for parallel up-/ download of data via WiFi/HSDPA (Nexus S). CNSM/SETM Workshop , Zürich, Switzerland 2

4 Approach (1/2) Reciprocal Scheme with Virtual Nodes =balanced link = consume = contribute =balanced link =possibly unblanced link Approach preserves game-theoretic properties Assuming nodes in virtual node trust each other Can be proven formally while virtual node can represent multiple nodes. More flexibility Allows for load balancing within virtual node CNSM/SETM Workshop , Zürich, Switzerland 3

5 Approach (2/2) Reciprocal Scheme with Virtual Nodes Cloud/CDN Instance = consume = contribute Trusted Nodes Allows projection of trust relations to the network Residential gateways Cloud instances =balanced link =possibly unblanced link CNSM/SETM Workshop , Zürich, Switzerland 4

6 Algorithms Token-trading Algorithm B 4 1 A B 5 3 C 2 1 A 2 1. A sends data to B 2. B sends data to A If B does not cooperate, A stops cooperation. Standard Tit-for- Tat 1. A sends data to C 2. B sends token to A 3. A sends token to B 4. B sends token to C 5. C sends data to B If C does not cooperate, A stops cooperation. 3 B A C D 1. A sends data to D 2 2. D sends token to A,C 3. A sends token to B 4. B sends token to C 5. C sends data to B If C does not cooperate, A stops cooperation. CNSM/SETM Workshop , Zürich, Switzerland 7

7 Preliminary Results (1/2) Evaluation Scenario Cloud Instance = consume = contribute Gateway-based streaming architecture Users streaming on their mobile phones via 3G can seek assistance of residential gateways to prevent upload =balanced link =possibly unblanced link CNSM/SETM Workshop , Zürich, Switzerland 9

8 Preliminary Results (2/2) Simulation Setup Simulation Setup Streaming system: mesh/pull-based Bandwidth model: based on [3] Video Model: 304/500/705/905 kbit/s Workload model: 2500 conventional peers/200 virtual nodes/500 peers online at the same time/session lengths based on [4] Results Free riding peers are punished efficiently Conventional peers and virtual nodes get constant playback quality Mobiles did not upload any video data Constant quality within virtual nodes Penalized free riders Played out seconds per minute/node type under varying number of free riders. CNSM/SETM Workshop , Zürich, Switzerland 10

9 Conclusions and Outlook Conclusions Reciprocity with virtual nodes is feasible in Peer-to- Peer streaming systems Resource-poor nodes can be supported efficiently Outlook Video-on-Demand Converged cloud/cdn/p2p scenarios Freemium business models Scheme allows to project trust relations to the network Clustering according to social data CNSM/SETM Workshop , Zürich, Switzerland 11

10 Thank You for Your Attention Department of Electrical Engineering and Information Technology Peer-to-Peer Systems Engineering PS Multimedia Communications Lab - KOM Dipl.-Wirtsch. Inf. Matthias Wichtlhuber mwichtlh@ps.tu-darmstadt.de Rundeturmstr Darmstadt Germany Phone +49 (0) 6151/ Fax +49 (0) 6151/ CNSM/SETM Workshop , Zürich, Switzerland 12

11 References [1] Sandvine: Fall 2012 Global Internet Phenomena Report. Technical Report, [2] Zinner, T., Abboud, O., Hohlfeld, O., Hoßfeld, T., and Tran-Gia, P.: Towards QoE Management for Scalable Video Streaming. ITC Specialist Seminar on Multimedia Applications - Traffic, Performance and QoE, [3] Organisation for Economic Co-operation and Development: OECD Broadband Report. Technical Report, [4] Vu, L., Gupta, I., Nahrstedt, K., and Liang, J.: Understanding Overlay Characteristics of a Large-Scale Peer-to-Peer IPTV System. ACM Transactions on Multimedia Computing, Communications, and Applications, vol. 6, no. 4, pp. 1-24, CNSM/SETM Workshop , Zürich, Switzerland 13