Technion

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Technion Israel Institute of TechnologySoftware
Systems Laboratory
A Comparison of Peer-to-Peer systems

• by Gomon Dmitri and Kritsmer Ilya
• under Roi Melamed supervising
• Winter Semester 2003

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Peer-to-Peer (P2P) Networks

• Gnutella like network
• Large number of similar nodes - no centralization
• Dynamic network.
• The search problem -nodes search for resources in
  the network.
• The problem is not addressed well by most popular
  systems currently in use.

The suggested solution

• Network is should not be overloaded by flood
  messages.
• Random Walker each search message received is
  forwarded to 1 random neighbor.
• Replication scheme enhances overall success rate.

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• Various replication strategies
• Owner replication when a search is
  successful, the object is stored at the requester
  node only. One can call this strategy as No
  Replication.
• Path replication when a search is successful,
  the pointer to the object is stored at all
  nodes along the path from the requester to the
  provider, and the object is stored at the
  requester node .
• Random replication when a search is
  successful, we count the number of nodes on the
  path between the requester and the provider and
  then randomly pick the same number of nodes and
  replicate the object. The most effective strategy.

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The Goal of the Project

• Implementation of the query algorithm based on
  multiple random walks with distinct replication
  modes, applied in Gnutella-like P2P networks
• Execution of simulations with various parameters.
• Analysis of the results.