1 / 18

Outline

Issues in Offering Live P2P Streaming Service to Residential Users Nazanin Magharei, * Yang Guo , and Reza Rejaie Dept. of Computer and Information Science *Princeton CR Lab University of Oregon Thomson Inc. Outline. Introduction and related work

maili
Download Presentation

Outline

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Issues in Offering Live P2P Streaming Service to Residential UsersNazanin Magharei, *Yang Guo, and Reza Rejaie Dept. of Computer and Information Science *Princeton CR Lab University of Oregon Thomson Inc.

  2. Outline • Introduction and related work • PRIME: Mesh-based P2P streaming service • Issues in offering p2p streaming to residential users • Effect of available resource • Effect of heterogeneous bandwidth • Effect of freeloaders • Effect of number of users • Conclusions and summary

  3. Introduction • P2P technique attracting attentions from commercial world • NBC Universal goes peer-to-peer – wurldmedia.com • BitTorrent raised $8.75 million venture capitals • Teamed with CacheLogic to work for BT • Startups providing P2P live program: pplive, coolstreaming • BBC IMP • Why? • Reduce the cost to compete with piracy • Conceivably provide p2p live streaming in a commercial setting • Using mesh-based p2p streaming

  4. Introduction • P2P live streaming • Tree-based approach • ESM, SplitStream, etc. • Mesh-based approach • Coolstreaming, Chainsaw, PRIME, etc. • Fundamental difference – static mapping of content to delivery topology vs. dynamic mapping

  5. Introduction and Related Work • Challenges • Heterogeneous access speed – DSL, cable modem, … • Insufficient resource • Asymmetric bandwidth – uplink bandwidth < downlink bandwidth • Free-loaders • Not willing to contribute • Cannot contribute • Behind NAT box or firewall • Key questions • What is the impact of available resource to overall performance? • How similar (different) is such an effect across peers with different bandwidth? • Whether and how the freeloaders affect the overall performance and individual received quality?

  6. PRIME: Mesh-based P2P Streaming Service • Peer expects to receive maximum deliverable quality through its access link • Using MDC in content delivery • Two possible performance bottlenecks • Bandwidth bottleneck • Insufficient aggregate bandwidth from all parents • Content bottleneck • Insufficient useful content from all parents • PRIME attempts to minimize these bottlenecks

  7. Global Pattern of Content Delivery Source • Connections in the overlay have roughly the same bandwidth • Group peers into levels, based on their shortest distance from source • Each peer with degree d in level n has at least one parent in level n-1 (diffusion parent) and d-1 parents in the same or lower levels (swarming parents) Level 1 1 3 2 Level 2 depth 4 6 5 7 10 12 8 13 9 11 Level 3

  8. Diffusion phase Peers should receive a data unit as fast as possible Swarming phase Peers exchange (swarm) data units with each other until receive their desired quality of the segment Global Pattern of Content Delivery SRC Level 1 1 3 2 4 6 Level 2 5 7 10 Level 3 12 8 13 9 11

  9. Simulation Setting • Evaluated using ns with congestion control • Network topology generated using Brite • Video rate of 400 kbps, downlink bandwidth of 550 kbps • Various resource distribution

  10. Effect of Available Resource Avg. received quality Resource Index CDF of received quality Average received quality is proportional to the resource index, however the individual received quality is random

  11. Effect of Heterogeneous Bandwidth Avg. received quality CDF of received quality Upload bandwidth • Bandwidth heterogeneity has no impact on the peers’ received quality • No correlation between received quality and resource contribution

  12. Effect of Free-loaders Free-loaders degrade the connectivity between different diffusion trees, hence prevent content swarming and limit delivery quality

  13. Effect of Number of Users

  14. Summary • Two issues identified • In resource poor scenarios, the delivered quality to peers is not correlated to their contribution • P2P streaming can handle heterogeneous bandwidth, however the presence of free-loaders significantly affect the mesh connectivity and degrade delivered quality • Solution: contribution-aware p2p streaming • Delivered quality is proportional to contribution • Encourage cooperation

  15. Backup Slides

  16. Global Pattern of Content Delivery SRC Level 1 1 3 2 4 6 Level 2 5 7 10 Level 3 12 8 13 9 11

  17. PRIME: Mesh-based P2P Streaming Service • Prior studies often assume a fix peer degree • Bandwidth bottleneck only depends on overlay topology • Incoming/outgoing bandwidth of participating peers • Incoming/outgoing degree of participating peers • Avg. BW for a connection between parent p and child c • MIN (outbwp/outdegp, inbwc/indegc) • All connections in the overlay have roughly the same bandwidth

More Related