Customizable%20Multicast%20Service%20using%20End%20System%20Multicast

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Customizable Multicast Service using End System
Multicast
Yang-hua Chu, Sanjay Rao, Srini Seshan, and Hui
Zhang, Carnegie Mellon University
Why not IP Multicast?
Customizable transport layer functionality

• Example functionality congestion control
• Can leverage existing unicast congestion control
  algorithm
• Run on every link of the overlay tree to
  determine acceptable data rate
• Example application conferencing
• Audio/video congestion control UDP (TFRC)
• Whiteboard TCP
• May use customized protocol for wireless links
  (compression, FEC, )

Application

• IP Multicast Problems
• Requires an ubiquitous infrastructure deployment
• Scalability with of groups
• Best effort service abstraction insufficient for
  most applications

?
?
IP
Network
Internet architecture
A new framework End System Multicast
200Kbps
CMU
MIT
Source rate(1Mbps)
Stanford
MIT
1Mbps
CMU
MIT
Berkeley
40Kbps

Stanford (wireless)
Berkeley
CMU
Berkeley
Customizable resource management
Stanford

• Benefits
• Scalability routers do not maintain per-group
  state
• Easy to deploy
• Allow application-specific customization
• Use hop-by-hop unicast forwarding
• Can leverage computation and storage at end
  systems

• Example resource available bandwidth
• Bandwidth shared by one multicast session and
  across multiple simultaneous sessions
• Changes dynamically
• Heterogeneous receivers
• Example application conferencing
• Multiple application streams per session
• Suboptimal if drop data packets indiscriminately
• Approach prioritize one data stream over another

ESM is a promising alternative!

• Key contributions from Sigmetrics00 Sigcomm
  01
• Narada a robust self-organizing protocol for
  constructing efficient overlay trees
• Bandwidth latency performance of basic ESM
  service is comparable to IP Multicast

Type Priority Bandwidth
whiteboard high 5Kbps
audio 45Kbps
video low 150Kbps
video low 800Kbps
Encoded in layers or encoded separately
Source rate(1Mbps)
200Kbps
CMU
MIT
1Mbps
IP Multicast Narada Random overlay
Berkeley
(Internet evaluation of 13 hosts, single source
at 1.2Mbps)
40Kbps
Stanford (wireless)