BiChord: An Improved Approach for Lookup Routing in Chord

  • Junjie Jiang
  • Ruoyu Pan
  • Changyong Liang
  • Weinong Wang
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3631)


Efficient resource lookup is essential for peer to peer networks and DHT (Distributed Hash Table) provides an ideal solution for resource lookup in distributed networks. Chord is a representative peer to peer lookup service based on DHT. The topology of Chord is modeled as a directed graph. There is a unidirectional link from a node to its every routing table entry node.

In this paper, we propose to model the topology of Chord as a bidirectional graph. A reverse link is added for each original unidirectional link and such a pair of symmetrical links is maintained by a single heart-beat message. Then each node should maintain a finger table and a reverse finger table at very little additional cost. However, such reverse fingers may help to improve the lookup efficiency greatly. Theoretical analyses and experimental results both approve such improvements.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2005

Authors and Affiliations

  • Junjie Jiang
    • 1
  • Ruoyu Pan
    • 2
  • Changyong Liang
    • 2
  • Weinong Wang
    • 3
  1. 1.Department of Computer Science and EngineeringShanghai Jiaotong UniversityShanghaiP.R. China
  2. 2.Institute of Network and SystemHefei University of TechnologyHefeiP.R. China
  3. 3.Network CenterShanghai Jiaotong UniversityShanghaiP.R. China

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