Keyword Search in Unstructured Peer-to-Peer Networks

  • Dingyi Han
  • Yong Yu


Keyword search is a preliminary application for peer-to-peer (P2P) networks. It is important for users to find relevant resources in the highly dynamic system. Many factors affect the results of keyword search, including the underlying structure of peer-to-peer network, the dynamics of peers, the distribution of resources, etc.

This chapter introduces the methods used for keyword search in unstructured peer-to-peer networks, and further discusses their extensions for multi-keyword search. These methods can be categorized into two types. One is blind routing. Methods of this type do not consider the distribution of resources. Hence, they get the name of “blind routing”. These methods are typically robust. However, their network traffics are high. The other is routing indices. Methods of this type exploit the distribution of resources or query keywords. Therefore, they have low network traffic, especially for popular resources or queries.

For each method, an algorithm flow is presented, followed by an analysis of the pros and cons. A comparison is also made to demonstrate the differences between these methods.

At the end of this chapter, a discussion on extending the search methods to the multi-keyword search problem is held. The methods introduced in this chapter work differently in the multi-keyword search scenario. Some may need no adaption while some shall be modified for multi-keyword indices. The efficiencies of these methods in this problem are also considered and compared.


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  1. 1.
    Androutsellis-Theotokis, S., Spinellis, D.: A survey of peer-to-peer content distribution technologies. ACM Computing Survey 36(4), 335–371 (2004). DOI CrossRefGoogle Scholar
  2. 2.
    Baeza-Yates, R.A., Ribeiro-Neto, B.: Modern Information Retrieval. Addison-Wesley Longman Publishing Co., Inc., Boston, MA, USA (1999)Google Scholar
  3. 3.
    Bloom, B.H.: Space/time trade-offs in hash coding with allowable errors. Communications of ACM 13(7), 422–426 (1970)MATHCrossRefGoogle Scholar
  4. 4.
    Carlsson, B., Gustavsson, R.: The rise and fall of napster - an evolutionary approach. In: AMT ’01: Proceedings of the 6th International Computer Science Conference on Active Media Technology, pp. 347–354. Springer-Verlag, London, UK (2001)Google Scholar
  5. 5.
    Chawathe, Y., Ratnasamy, S., Breslau, L., Lanham, N., Shenker, S.: Making gnutella-like p2p systems scalable. In: SIGCOMM ’03: Proceedings of the 2003 conference on Applications, technologies, architectures, and protocols for computer communications, pp. 407–418. ACM, New York, NY, USA (2003). DOI
  6. 6.
    Crespo, A., Garcia-Molina, H.: Routing indices for peer-to-peer systems. In: ICDCS ’02: Proceedings of the 22 nd International Conference on Distributed Computing Systems (ICDCS’02), p. 23. IEEE Computer Society, Washington, DC, USA (2002)Google Scholar
  7. 7.
    Gkantsidis, C., Mihail, M., Saberi, A.: Random walks in peer-to-peer networks. In: INFOCOM 2004. Twenty-third AnnualJoint Conference of the IEEE Computer and Communications Societies, pp. 120–130 (2004)Google Scholar
  8. 8.
    Jiang, S., Guo, L., Zhang, X.: Lightflood: an efficient flooding scheme for file search in unstructured peer-to-peer systems. In: Proceedings. 2003 International Conference on Parallel Processing, pp. 627–635 (2003)Google Scholar
  9. 9.
    Klemm, A., Lindemann, C., , Waldhorst, O.: Relating Query Popularity and File Replication in the Gnutella Peer-to-Peer Network. In: Proceedings 12th GI/ITG Conference on Measuring, Modelling and Evaluation of Computer and Communication Systems (MMB). Dresden, Germany (2004)Google Scholar
  10. 10.
    Kumar, A., Xu, J., Zegura, E.: Efficient and scalable query routing for unstructured peer-to-peer networks. INFOCOM 2005. 24th Annual Joint Conference of the IEEE Computer and Communications Societies. Proceedings IEEE 2, 1162–1173 (2005)Google Scholar
  11. 11.
    Lv, Q., Cao, P., Cohen, E., Li, K., Shenker, S.: Search and replication in unstructured peer-to-peer networks. In: ICS ’02: Proceedings of the 16th international conference on Supercomputing, pp. 84–95 (2002)Google Scholar
  12. 12.
    Meng, S., Shi, C., Han, D., Zhu, X., Yu, Y.: A statistical study of todays gnutella. Lecture Notes in Computer Science 3841/2006, 189–200 (2006)Google Scholar
  13. 13.
    Milgram, S.: The small world problem. Psychology Today 2,60–67 (1967)Google Scholar
  14. 14.
    Mitchell, T.M.: Machine Learning. McGraw-Hill Higher Education (1997)Google Scholar
  15. 15.
    Ripeanu, M.: Peer-to-peer architecture case study: Gnutella network. p. 99. IEEE Computer Society, Los Alamitos, CA, USA (2001)Google Scholar
  16. 16.
    Ripeanu, M., Foster, I., Iamnitchi, A.: Mapping the gnutella network: Properties of large-scale peer-to-peer systems and implications for system design. IEEE Internet Computing Journal 6, 50–57 (2002)Google Scholar
  17. 17.
    Shi, C., Han, D., Liu, Y., Meng, S., Yu, Y.: A dynamic routing protocol for keyword search in unstructured peer-to-peer networks. Journal of Computer Communications 31(2), 318–331 (2008). DOI CrossRefGoogle Scholar
  18. 18.
    Shi, C., Meng, S., Liu, Y., Han, D., Yu, Y.: Reinforcement learning for query-oriented routing indices in unstructured peer-to-peer networks. p2p 0, 267–274 (2006)Google Scholar
  19. 19.
    Tsoumakos, D., Roussopoulos, N.: Adaptive probabilistic search for peer-to-peer networks. In: P2P ’03: Proceedings of the 3rd International Conference on Peer-to-Peer Computing, p. 102. IEEE Computer Society, Washington, DC, USA (2003)Google Scholar
  20. 20.
    Tsoumakos, D., Roussopoulos, N.: Analysis and comparison of p2p search methods. In: InfoScale ’06: Proceedings of the 1st international conference on Scalable information systems, p. 25. ACM, New York, NY, USA (2006). DOI

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© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  1. 1.Apex Data & Knowledge Management Lab, Department of Computer Science & EngineeringShanghai Jiao Tong UniversityShanghaiChina

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