Information Technology Reference
In-Depth Information
Source
M
M
M
Stripeld 0x
Stripeld 1x
Stripeld Fx
Nodelds starting 0x
Nodelds starting 1x
Nodelds starting Fx
Nodelds starting 2x..Ex
Figure 1.17
SplitStream's forest construction. Each stripeId starts with a different digit. The nodeIds of
interior nodes share a prefix with the stripeId, thus they must be leaves in the other trees.
(From Castro, M., Druschel, P., Kermarrec, A.-M., Nandi, A., Rowstron, A., and Singh, A.,
Proceedings of the 19th ACM Symposium on Operating Systems Principles, October 19-22,
2003. With permission.)
Distributed streaming application (promise)
Redistribute Rates
Rate/data
assignment
Monitoring and
adapatation
Active, rates
Active Set
Switch Peers
Topology
inference and
labeling
Peer selection
Annotated
Topology
Candidate Set
Peer-to-Peer lookup substrate (pastry)
Figure 1.18
Components of CollectCast. (From Hefeeda, M., Habib, A., Xu, D., Bhargava, B., and Botev, B.,
ACM Multimedia Systems J.,
11(1), 68-81, November 2005. With permission.)
PROMISE is a P2P media streaming system intended for on-demand video
playback that enables one receiver to collect data from multiple senders. PROMISE
is based on a P2P service called CollectCast. CollectCast bridges PROMISE and
DHT-based structures and performs three major functions: selecting peers
based on the inferred underlying network topology, monitoring the status of
the peers, and dynamic switching of the active and standby peers.
Figure 1.18 shows the components of CollectCast and the interactions
among them. The P2P lookup substrate could be Pastry, CAN, or Tapestry.
PROMISE outlines some good policies for peer selections and dynamic
adaptation. However, it is mainly used for on-demand video playback. Even
