[p2p][paper reading]Peer-to-Peer Live Video Streaming on the Internet:Issues, Existing Approaches, and Challenges

出處:
IEEE communication magazine  .June 2007

筆記:
[Video Streaming challenges]

• High bit rate


• End-to-End delay requirement


• Packet loss


• Network congestion


• Stream Synchronization


• Lake of  service guarantee

[Encoding Perspective]

• layered-base coding ->Heterogeneity dynamic


• Error-resilient codec->Packet loss

[Internet]

• Multicast->Reduce duplication of data


• CDN (content distributed network) ->Reduce end-to-end delay

[observation]Many other factor can be more easily dealt with

• TCP->用於streaming可解決packet loss的問題


• multi-segment and multi-path routing ->reduce congestion

[Key feature in p2p system]

• Each node contributes resources (more node can increase system capacity)
  
  
  
  • bandwidth
  
  
  • storage
  
  
  • computing power


• Robustness
  
  
  
  • 不依賴centralized server

[Multi-rate Multicast]

• IP  Multicast
  
  
  
  • Each link only once with out duplication
  
  
  • Problem
    
    
    
    • Heterogeneity -> 不同device的能力不同
    
    
    • Dynamic ->Best effort Internet video撥放的品質變化大
    
    
    • RLM用來解決此問題->send video layer over different group 使用者訂閱要看的group


• Application Multicast
  
  
  
  • 把multicast tree放到applicatino layer 所以作multicast可以不用infrastructure 支援
  
  
  • Issues
    
    
    
    • How to build a  stable overlay network in the presence of dynamics in the overlay network
    
    
    • Appropriate routing scheme->use in overlay network
    
    
    • How to self-organization and self-adapt to the changing  topology
  
  
  • Important requirement
    
    
    
    • 足夠的resource for overlay construction
    
    
    • Inherent stability
    
    
    • Can potentially support large scale