UnFileSharing Technologies

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(No Transcript)
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Understanding File Sharing Technologies

• Typical Client-Server Model
• Peer-to-Peer Technology
• Napster, Grokster, StreamCast, and Beyond

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Typical Client-Server Technology

• World Wide Web example

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Peer-to-Peer Technology

• Involves transfer of files among multiple
  clients, rather than solely from servers to
  clients.
• Software converts ordinary machines into
  mini-servers.
• Napster pioneered this concept Grokster and
  StreamCast reflect variations on the model.

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Napster Central Server Model
Napsters Central Indexing Servers
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Napster Central Server Model
Napsters Central Indexing Servers
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Napster Central Server Model
Napsters Central Indexing Servers
File Exchange
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Alternative Peer-to-Peer Models
Alternative models do not rely as heavily on
central servers central servers may provide
software, but they do not index files.
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Alternative Peer-to-Peer Models
Computers contact other computers directly, based
on addresses programmed into software.
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Alternative Peer-to-Peer Models
Song request propagates among other computers
until match is found.
Song Request
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Alternative Peer-to-Peer Models
Transfer occurs between computers, without
central server involvement.
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Grokster and StreamCast Distinguished
Grokster employs supernode technology, where a
number of larger computers perform indexing
functions.
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Grokster and StreamCast Distinguished
Supernode
Supernode
Supernode
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Grokster and StreamCast Distinguished
Supernode
Supernode
Supernode
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Grokster and StreamCast Distinguished
Supernode
Supernode
Supernode