Unstructured Peer-to-Peer Networks: Topological Properties and Search Performance

  • George H. L. Fletcher
  • Hardik A. Sheth
  • Katy Börner
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3601)


Performing efficient decentralized search is a fundamental problem in Peer-to-Peer (P2P) systems. There has been a significant amount of research recently on developing robust self-organizing P2P topologies that support efficient search. In this paper we discuss four structured and unstructured P2P models (CAN, Chord, PRU, and Hypergrid) and three characteristic search algorithms (BFS, k-Random Walk, and GAPS) for unstructured networks. We report on the results of simulations of these networks and provide measurements of search performance, focusing on search in unstructured networks. We find that the proposed models produce small-world networks, and yet none exhibit power-law degree distributions. Our simulations also suggest that random graphs support decentralized search more effectively than the proposed unstructured P2P models. We also find that on these topologies, the basic breadth-first search algorithm and its simple variants have the lowest search cost.


Search Algorithm Network Size Random Graph Degree Distribution Topological Property 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2005

Authors and Affiliations

  • George H. L. Fletcher
    • 1
  • Hardik A. Sheth
    • 2
  • Katy Börner
    • 3
  1. 1.Computer Science DepartmentIndiana UniversityBloomingtonUSA
  2. 2.School of InformaticsIndiana UniversityBloomingtonUSA
  3. 3.School of Library and Information ScienceIndiana UniversityBloomingtonUSA

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