1. End-to-end QoE Optimization Through Overlay Network Deployment Bart De Vleeschauwer, Filip De Turck, Bart Dhoedt and Piet Demeester Ghent University - Department of Information Technology Maarten Wijnants and Wim Lamotte Hasselt University - Expertise Centre for Digital Media

2. End-to-end QoE Optimization Through Overlay Network Deployment 23/01/2008 ICOIN20082 Outline Introduction & Motivation Overlay Network Architecture –Architectural Overview –Overlay server –Overlay access component –Network Intelligence Proxy Evaluation –Evaluation Testbed –Experimental Results Conclusions

3. End-to-end QoE Optimization Through Overlay Network Deployment Introduction & Motivation Continuous rise in usage Internet for multimedia services –E.g. IPTV, Skype, online gaming Multimedia services are more sensitive to packet loss, bandwidth restrictions, delay and jitter –Network performance guarantees required Failure to meet requirements will have impact on user Quality of Experience –E.g. jitter in VoIP = varying response times 23/01/2008 ICOIN20083

4. End-to-end QoE Optimization Through Overlay Network Deployment Introduction & Motivation Internet is currently not able to provide any performance guarantees –Routing is best-effort Can result in suboptimal routing between hosts Solutions proposed to provide QoS (e.g. IntServ and DiffServ) still suffer from unresolved issues –Last mile can impose bandwidth bottleneck May result in congestion Increase in packet loss and packet delay possible  No E2E solution for QoE provision yet available 23/01/2008 ICOIN20084

5. End-to-end QoE Optimization Through Overlay Network Deployment End-to-end Architectural Overview 23/01/2008 ICOIN20085 Overlay layer Network layer Last mile QoE optimization

6. End-to-end QoE Optimization Through Overlay Network Deployment Overlay Server (OS) Monitors connectivity through active network probing –Deduce delay & packet loss on overlay edges Maintains a virtual topology using overlay routing tables (ORTs) –ORTs map target OS to next hop OS Overlay routing tables are adapted to reflect the current network condition Forwards overlay packets via “good” path  OSs provide resilient overlay routing 23/01/2008 ICOIN20086

7. End-to-end QoE Optimization Through Overlay Network Deployment Overlay Access Component (AC) Deployed at the edge of the network –End-device, residential gateway, … Monitors quality of connection (i.e. packet loss & delay) between source-destination Packets are pushed to overlay layer in case of problematic direct IP connection –Packets pushed to closest OS –OS forwards packets to AC close to target –AC transfers packets back to IP network layer  Transparent access to overlay network 23/01/2008 ICOIN20087

8. End-to-end QoE Optimization Through Overlay Network Deployment Overlay Routing Example 23/01/2008 ICOIN20088

9. End-to-end QoE Optimization Through Overlay Network Deployment Network Intelligence Proxy (NIProxy) Optimizes last mile content delivery to clients –Through awareness introduction in network Both network- and application-related context Provides client bandwidth management –Through creation stream hierarchy Acts as service provision platform –Supports processing of multimedia flows –Through generic plug-in approach –E.g. video transcoding plug-in 23/01/2008 ICOIN20089

10. End-to-end QoE Optimization Through Overlay Network Deployment Evaluation Testbed Setup with 10 Linux PCs Core network and last mile impairment are emulated using Click nodes 23/01/2008 ICOIN200810

11. End-to-end QoE Optimization Through Overlay Network Deployment Experimental Results – Resilient Overlay Routing Packet loss ratio per sec during 50 secs, with and without overlay routing 10% average loss OR: packet loss circumvented SR: packet loss, resulted in visual artifacts at client-side 23/01/2008ICOIN200811

12. End-to-end QoE Optimization Through Overlay Network Deployment Experimental Results – Last Mile QoE Optimization NIProxy managed last mile video delivery Experiment consisted of 5 intervals –Caused by both bandwidth fluctuations and client-initiated shifts in stream importance 23/01/2008 ICOIN200812 Finding 2: more bw for important streamsFinding 1: downstream capacity respected No NIProxy: less optimal QoE, e.g. video hitches

13. End-to-end QoE Optimization Through Overlay Network Deployment Conclusions Overlay network for E2E QoE management –Components in network core and at edge –Improves standard network routing service –Last mile QoE optimization Results illustrate effectiveness of approach –Complementarity constituting components –Elimination/decrease packet loss using resilient overlay routing (e.g. avoiding failing links) –Last mile congestion avoidance through intelligent bandwidth management and multimedia service provision 23/01/2008 ICOIN200813

14. End-to-end QoE Optimization Through Overlay Network Deployment Thank you for your attention! Any questions?