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2/32. Introduction. Nation-wide TV broadcastSatellite-based Terrestrial-based (typically over IP networks ? IPTV)IPTV architectural design Integrate IPTV services with existing IP backboneConstruct a dedicated overlay network on top of IPConstruct a direct interconnected flat IP networkIntegrate with an existing switched optical network.
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1. 1/32 Case Study: Resilient Backbone Design for IPTV Services Meeyoung Cha, Gagan Choudhry, Jennifer Yates, Aman Shaikh and Sue Moon
Presented by Yuanbin Shen
March 25, 2009
2. 2/32
3. 3/32 Overview of IPTV Architecture
4. 4/32 IPTV Traffic Type
Broadcast TV: realtime
VoD download: non-realtime download to VHOs
Realtime VoD: realtime
Characteristics
Uni-directional and high-bandwidth
VoD traffic: highly variable
Multicast for broadcast TV / unicast for VoD
5. 5/32 Design Options Technology:
layer1 (optical) v.s. layer3 (IP/MPLS)
Topology:
hub-and-spoke v.s. meshed
6. 6/32 Design Options (contd)
7. 7/32 Model 1: Integrate With Existing IP Backbone Backbone links are shared and access links are dedicated
Rapid deployment: using existing infrastructure
High resource utilization: share bandwidth between applications
Drawback: IPTV quality easily impacted by Internet traffic
8. 8/32 Model 2: Dedicated Overlay Use common backbone routers to construct dedicated IPTV overlay
Easy for performance management: links are dedicated
Overhead to construct the overlay
9. 9/32 Model 3: Flat IP (No backbone) Services routers (SR) directly connected using point-to-point links
over dense wavelength division multiplexors (DWDMs)
Connect geographically close VHOs into regional rings
Inter-connect rings with long super links
No existing infrastructure used
10. 10/32 Model 4: Integrate with switched optical network Multicast capabilities at optical nodes (new technology)
SHOs establish multicast trees, VHO receiving single best stream
Failure recovery: rapid switch between different paths
How to find physically-diverse paths from SHOs to each VHO?
? NP-hard ? use IP-based approach to create trees
11. 11/32 Design Instances
12. 12/32 Evaluation- Cost (capital) comparison of multicast and unicast Multicast is much more economical than unicast
Optical network is more economical than IP network
13. 13/32 Evaluation- Cost (capital) comparison across design instances Optical networks are more economical than IP networks
Total cost is dominated by access cost (except for IP flat design)
Ring access is good of multicast; dual-homed access is good for unicast(VoD)
For backbone cost, the flat IP model is the most expensive
14. 14/32 Conclusion Explore potential IPTV designs in backbone network
Comparison across different design architectures
Significant benefits of using multicast for broadcast TV
Optical design more economical than IP designs
Ring access attractive for broadcast TV; dual-homed access attractive for VoD
15. 15/32 When is P2P Technology Beneficial for IPTV Services? Yin-Farn Chen, Yennun Huang, Rittwik Jana, Hongbo Jiang, Michael Rabinovich, Bin Wei and Zhen Xiao
Presented by Yuanbin Shen
March 25, 2009
16. 16/32 Introduction Problems in providing IPTV:
high deployment and maintenance cost
Server bandwidth limits
One solution ? using P2P technology
Does P2P technology always works well for IPTV? When is it beneficial?
Network models
Cloud model: overestimate P2P benefits
Physical model: more practical
Provide three incentive models to encourage P2P sharing in IPTV under a physical model
17. 17/32 Cloud Model Simple for modeling
Does not consider the constraints of the underlining service infrastructure
18. 18/32 Physical Model
19. 19/32 P2P Sharing within a Community
20. 20/32 P2P Sharing within a Community
21. 21/32 P2P Sharing across Communities
22. 22/32 Simulation Setup
23. 23/32 Simulation Setup
24. 24/32 Results: cloud model v.s. physical model -1
25. 25/32 Results: cloud model v.s. physical model -2
26. 26/32 Results: cloud model v.s. physical model -3
27. 27/32 Cost-Benefic Analysis Maximum Profit for Conventional IPTV
Pnop2p = rN Enop2p
P2P Incentive Models
Built-in Model:
Pb = rN Enop2p tN
r: fee paid by a viewer
N: number of viewers
tN: P2P installation expense
28. 28/32 Cost-Benefic Analysis Flat-reward Model:
Pf = rN Enop2p twN dwN
w: percent of viewers sign up for P2P
d: reward per P2P user
Usage-based Model
Ps = rN Enop2p tN qbuTN
u: average video rate
T: program length
q: credit per bit
b: percent of viewers download data from peers
29. 29/32 Profit Per Unit Time
30. 30/32 Simulation Results (Using MediaGrid Algorithm)
31. 31/32 Conclusion Studied when P2P is beneficial for IPTV
Cloud model may overstate P2P benefits ? use physical model
Different incentive strategies lead to different profits ? choose a proper one for specific application.
32. 32/32 References M. Cha, G. Choudhury, J. Yates, A. Shaikh, and S. Moon, Case Study: Resilient Backbone Design for IPTV Services, In Proc. of International Workshop on Internet Protocol TV Services over World Wide Web, May 2006
M. Cha, G. Choudhury, J. Yates, A. Shaikh, and S. Moon, Slides: http://an.kaist.ac.kr/~mycha/docs/mycha_www_iptv06.ppt
Y. Chen, Y. Huang, R. Jana, H. Jiang, M. Rabinovich, B. Wei, and Z. Xiao, When is P2P Technology Beneficial for IPTV Services, ACM NOSSDAV, June 2007.
Meng-Ting Lu, Slides: When is P2P Technology Beneficial for IPTV Services, http://nslab.ee.ntu.edu.tw/OESeminar/slides/When is P2P Technology Beneficial for IPTV Services.ppt