1. Effective and Resource-Efficient Multimedia Communication Using the NIProxy Maarten Wijnants and Wim Lamotte Hasselt University - Expertise Centre for Digital Media

2. Effective and Resource-Efficient Multimedia Communication Using the NIProxy Introduction and Motivation Increasing interest in multimedia services such as VoIP, real-time videostreaming, … –Require high, guaranteed performance levels from communication network –Raise need for network resource management  Both issues often not addressed/supported by current-gen networks Networks faced with growing diversity, e.g. –Proliferation of new networking technologies and protocols –Heterogeneity in client device space 23/06/2008 ADAMUS20082

3. Effective and Resource-Efficient Multimedia Communication Using the NIProxy Introduction and Motivation Next-gen networks should –Provide adequate, resource-efficient support for multimedia communication –Be able to successfully cope with heterogeneity Design/deploy from scratch: Expensive! Extend functionality current networks with next-gen features: Cost-efficient (reuse)! NIProxy: Network intermediary –Enhances IP-based networks with functionality to improve MM communication 05/03/2009 ICN20093

4. Effective and Resource-Efficient Multimedia Communication Using the NIProxy Outline Introduction and Motivation Network Intelligence Proxy (NIProxy) –Objectives and methodology –Support for upstream/outbound network traffic Practical Use Case: Outbound Video Transcoding Evaluation of Proposed NIProxy Extensions –Experimental Setup –Experimental Results Conclusions 23/06/2008 ADAMUS20084

5. Effective and Resource-Efficient Multimedia Communication Using the NIProxy Network Intelligence Proxy (NIProxy) Goal = Improve user Quality of Experience –Note: QoE != Quality of Service (QoS) ! Approach = Incorporate intelligence/ awareness in transportation network –Network- as well as application-related context Info about transportation network state (probing) Knowledge of the networked application Intelligence enables NIProxy to implement effective/efficient MM data dissemination –Network traffic shaping & MM service provision  Complementary techniques, interoperable 05/03/2009 ICN20095

6. Effective and Resource-Efficient Multimedia Communication Using the NIProxy Network Intelligence Proxy (NIProxy) NIProxy is under continuous development –Traffic shaping & service provision previously confined to downstream/inbound direction –Now extended to upstream/outbound direction 05/03/2009 ICN20096 DownstreamUpstream Processing location Near end of MM stream’s network traversal Beginning of MM stream’s network traversal Flow source Destined for NIProxy client Emitted by NIProxy client

7. Effective and Resource-Efficient Multimedia Communication Using the NIProxy Practical Use Case: Outbound Video Transcoding Enables NIProxy to on-the-fly reduce bitrate of outbound video streams at early stage of video flow network traversal –Decreases temporal resolution & increases compression ratio (larger quantization step) Mode of operation –In = Outbound video at original quality –Out = Original version or transcoded variant –Based on video source’s upstream bandwidth distribution strategy devised by NIProxy –Unnecessary transcoding operations eliminated 05/03/2009 ICN20097

8. Effective and Resource-Efficient Multimedia Communication Using the NIProxy Practical Use Case: Outbound Video Transcoding Exemplifies interoperation possibilities between traffic shaping & service provision and the positive implications it entails –Service introduces new type of network flow –Ensures it is represented in video source’s upstream network traffic shaping scheme –Once incorporated, it is considered during management of source’s upstream BW capacity –NIProxy’s network traffic shaping scheme subsequently dictates outbound video transcoding decisions 05/03/2009 ICN20098

9. Effective and Resource-Efficient Multimedia Communication Using the NIProxy Evaluation Goal = Investigate added value outbound network traffic shaping & service provision Experimental setup: Simulation of unicast MM streaming scenario Involved several (distributed) entities –Single streaming server, multiple clients –NIProxy: Shaped server emitted traffic –WAN BW broker: Managed BW capacity of the network backbone Determined amount of backbone BW the streaming server could maximally consume (e.g. SLA-based) 05/03/2009 ICN20099

10. Effective and Resource-Efficient Multimedia Communication Using the NIProxy Evaluation 05/03/2009 ICN200910 MM server & clients deployed in separate access networks  Server’s outbound network traffic consumed backbone bandwidth NIProxy deployed at end of server’s access connection  Adapted/shaped server’s outbound network traffic before it reached the WAN

11. Effective and Resource-Efficient Multimedia Communication Using the NIProxy Evaluation: Minimalist Experiment MM server streamed video fragment + audio stream to single client –NIProxy responsible for apportioning WAN BW reserved for MM server over these 2 flows Fluctuations in server WAN BW capacity –Conceptually partitioned exp in # intervals Client preferred audio over video –Server made NIProxy aware of this app-related information  was taken into account when shaping the server’s upstream BW NIProxy used outbound video transcoding 05/03/2009 ICN200911

12. Effective and Resource-Efficient Multimedia Communication Using the NIProxy Evaluation: Minimalist Experiment Dashed vertical lines separate experiment intervals Bandwidth consumption: TV < audio < OV 05/03/2009 ICN200912 Analysis: WAN transmission of audio flow prioritized throughout entire experiment Analysis: BW left unused by audio employed to implement video streaming at highest quality possible

13. Effective and Resource-Efficient Multimedia Communication Using the NIProxy Evaluation: More Realistic Experiment Multiple simultaneous clients, each requested one video fragment from server Steady server WAN BW capacity Contracts between MM server and clients –Distinction regular/premium clients –Premium users should receive improved service Dynamic aspect: Arrival/departure of clients during experiment execution –Initiation/suspension outbound flows at runtime –Conceptually partitioned exp in # intervals 05/03/2009 ICN200913

14. Effective and Resource-Efficient Multimedia Communication Using the NIProxy Evaluation: More Realistic Experiment Dashed vertical lines separate experiment intervals Small transition period at start 4 th interval (non- optimal BW distr) 05/03/2009 ICN200914 Analysis: Client contracts were observed (server’s premium users received preferential treatment)

15. Effective and Resource-Efficient Multimedia Communication Using the NIProxy Evaluation: Experimental Findings MM server respected its WAN BW capacity –E.g. no SLA contract violation –Contributed to WAN stability and performance predictability  positive influence on user QoE NIProxy attempted to maximize the utility of the upstream BW allocated to server –WAN BW partitioned as intelligently/effectively as possible over server’s set of outbound flows Guided by app-awareness; Positively affected user QoE QoE-improvement collaboration beneficial –Lower-quality WAN video streaming possible 05/03/2009 ICN200915

16. Effective and Resource-Efficient Multimedia Communication Using the NIProxy Conclusions Popularity multimedia streaming rising –Support for effective and resource-efficient multimedia network communication required We therefore propose the NIProxy –Enhances IP-based network with traffic shaping and MM service provision functions Downstream/inbound as well as upstream/outbound Experimental evaluation demonstrated NIProxy benefits –MM capabilities of networks are improved –Positive impact on experience witnessed by users 05/03/2009 ICN200916

17. Effective and Resource-Efficient Multimedia Communication Using the NIProxy Thank you for your attention! Any questions?