Conclusions in Peer-to-Peer Systems

1
Conclusions in Peer-to-Peer Systems

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2
Advantages Disadvantages

• Advantages
• Scalability
• Easy and cheap to built
• Fault tolerance
• Load Balance
• Elimination of network bottlenecks
• Autonomy
• Availability
• Reliability
• No-administration
• Avoidance of legal constraints

• Disadvantages
• Complexity (join, look up)
• Incomplete look up
• Communication cost
• Network overhead
• Maintenance cost
• Security

3
Examples of Applications

• File sharing systems
• Kazaa, Gnutella, Soulseek, etc
• Distributed Computation
• Seti_at_Home
• Distributed Databases
• Data are spread across the network
• Cooperative Mirroring
• Load balance across all servers (using
  replication and caching)

4
Interesting Issues

• Chord Ring
• Simple topology, efficient look up and join,
  small routing information
• Routing Indices
• Alternative approach to flooding
• More efficient and less network overhead
• Shortcuts
• Connecting nodes with similar interests
• SONs
• Clustering nodes accordingly to their content
• Caching and replication
• Cached results for future use

5
Best Paper

• Chord A Scalable Peer-to-peer Lookup Service for
  Internet Applications
• Clever concept
• Simple structure (just a ring)
• Complete paper

6
Main Issues for Future Work

• Clustering techniques without a-priori knowledge
  of existing clusters
• Cycle prediction and elimination
• Unstructured systems (too many messages)
• Routing indices (inaccurate indices)
• Security
• Anonymity
• Authenticity

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• END