P2P (Peer-to-Peer) 系統的研究者常依照使用者的興趣來建立捷徑以加速搜
尋速率。然而，這樣的捷徑建立方式會因為網路本身的成長讓捷徑以指數方式成長。為了探討這個議題，我們試著將social network的概念導入點對點系統中。因此，本研究旨在如何利用各項social network的概念來加快P2P network系統的搜尋過程以增進的搜尋效率。
本論文提出利用P2P系統中已連接節點的本地資訊，經由各節點獨特的social network，發掘有用的資源(潛在的朋友)，進而建立捷徑。本研究旨在擴大搜尋的範疇以迎合各種查詢的需要且維持一定的效率。
本實驗的分析是採用模擬的方式進行，目的是釐清social network特性如何幫助P2P系統中的搜尋。研究結果顯示我們的假設與實驗結果具有某些程度的一致性。總結而言，此研究希望能解釋如何利用social network特性來加速P2P系統的搜尋過程。

Researchers of Peer-to-peer networks (P2P) have often suggested that using interest-based shortcuts
to accelerate the searching process. However, the number of shortcuts in the most proposed
techniques exponentially increases with the size of the interest set. To address this issue, we attempt
to adapt social network concepts into P2P systems. Therefore, the objective of the paper
is to explore how to apply social network concepts and how those concepts are used to speed up
P2P searching process.
This paper describes an approach that exploits the local information of current connecting
peers in P2P systems to discover usable resources (latent friends) via individual’s unique social
networks, and then establishing long paths with them. This research involved a goal to broaden
the search scope to cater various kinds of query properties with limited maintenance cost but still
with certain efficiency.
The analysis of the experiments was conducted through simulation in order to indicate the relationship
between social network and P2P systems. The experimental results show some degree
of consistence with our hypotheses. To conclude, this study may be of importance in explaining
how the characteristics of social networks are used to beef up the query process in P2P system.

[1] Karl Aberer, Magdalena Punceva, Manfred Hauswirth, and Roman Schmidt. Improving
data access in p2p systems. IEEE Internet Computing, 6(1):58–67, 2002.
[2] Lada A. Adamic. The small world web. In Serge Abiteboul and Anne-Marie Vercoustre,
editors, ECDL, volume 1696 of Lecture Notes in Computer Science, pages 443–452.
Springer, 1999.
[3] Lada A. Adamic, Rajan M. Lukose, Amit R. Puniyani, and Bernardo A. Huberman. Search
in power-law networks. CoRR, cs.NI/0103016, 2001.
[4] A.L. Barabasi, H. Jeong, Z. Neda, E. Ravasz, A. Schubert, and T. Vicsek. Evolution of the
social network of scientific collaborations. arXiv:cond-mat/0104162, 2001.
[5] Burton H. Bloom. Space/time trade-offs in hash coding with allowable errors. Commun.
ACM, 13(7):422–426, 1970.
[6] Arturo Crespo and Hector Garcia-Molina. Routing indices for peer-to-peer systems. In
ICDCS, pages 23–, 2002.
[7] Arturo Crespo and Hector Garcia-Molina. Semantic overlay networks for p2p systems.
In Gianluca Moro, Sonia Bergamaschi, and Karl Aberer, editors, AP2PC, volume 3601 of
Lecture Notes in Computer Science, pages 1–13. Springer, 2004.
[8] Lisa A. Ennis. Book review: Peer-to-peer: Harnessing the benefits of a disruptive technology,
edited by andy oram. JASIST, 52(13):1191–1192, 2001.
[9] K.M. Fairchild, S.E. Poltrock, and G.W. Furnas. SemNet: Three-Dimensional Representation
of Large Knowledge Bases. Lawrence Erlbaum Associates, Inc., 1988.
[10] Michalis Faloutsos, Petros Faloutsos, and Christos Faloutsos. On power-law relationships
of the internet topology. In SIGCOMM, pages 251–262, 1999.
[11] L. Freeman. A set of measures of centrality based upon betweenness. Sociometry, 40:35–
41, 1977.
[12] Gnutella. http://gnutella.wego.com.
[13] J. Guare. Six degrees of Separation: A Play. New York, 1990.
[14] P. Krishna Gummadi, Stefan Saroiu, and Steven D. Gribble. A measurement study of napster
and gnutella as examples of peer-to-peer file sharing systems. Computer Communication
Review, 32(1):82, 2002.
37
[15] Imad Jawhar and Jie Wu. A two-level random walk search protocol for peer-to-peer networks.
In Proceedings of the 8th World Multi-Conference on Systemics, Cybernetics and
Informatics., 2004.
[16] V. Kalogeraki, D. Gunopulos, and D. Zeinalipour-Yazti. A local search mechanism for peerto-
peer networks. In Proceedings of the eleventh international conference on Information
and knowledge management, pages 300–307. ACM Press, 2002.
[17] Kazaa. http://www.kazaa.com.
[18] Jon M. Kleinberg. Navigation in a small world. Nature, 406, 2000.
[19] Jon M. Kleinberg. The small-world phenomenon: an algorithm perspective. In STOC,
pages 163–170, 2000.
[20] Robert R. Korfhage. Information storage and retrieval. New York, 1997.
[21] Qin Lv, Pei Cao, Edith Cohen, Kai Li, and Scott Shenker. Search and replication in unstructured
peer-to-peer networks. In SIGMETRICS, pages 258–259. ACM, 2002.
[22] S. Milgram. The small world problem. PSYCHOLOGY TODAY, 22:61–67, 1967.
[23] Morpheus. http://www.musiccity.com.
[24] Napster. http://www.napster.com.
[25] Wolfgang Nejdl, BorisWolf, Changtao Qu, Stefan Decker, Michael Sintek, Ambj¨orn Naeve,
Mikael Nilsson, Matthias Palm´er, and Tore Risch. Edutella: a p2p networking infrastructure
based on rdf. In WWW, pages 604–615, 2002.
[26] M. E. J. Newman. The structure of scientific collaboration networks. Proc. Natl. Acad. Sci.,
98(404-409), 2001.
[27] PeerSim. http://peersim.sourceforge.net/.
[28] Murali Krishna Ramanathan, Vana Kalogeraki, and Jim Pruyne. Finding good peers in
peer-to-peer networks. In IPDPS. IEEE Computer Society, 2002.
[29] Sylvia Ratnasamy, Paul Francis, Mark Handley, Richard M. Karp, and Scott Shenker. A
scalable content-addressable network. In SIGCOMM, pages 161–172, 2001.
[30] Matei Ripeanu. Peer-to-peer architecture case study: Gnutella network. In Peer-to-Peer
Computing, pages 99–100, 2001.
[31] Matei Ripeanu, Ian T. Foster, and Adriana Iamnitchi. Mapping the gnutella network:
Properties of large-scale peer-to-peer systems and implications for system design. CoRR,
cs.DC/0209028, 2002.
[32] Antony I. T. Rowstron and Peter Druschel. Pastry: Scalable, decentralized object location,
and routing for large-scale peer-to-peer systems. In Rachid Guerraoui, editor, Middleware,
volume 2218 of Lecture Notes in Computer Science, pages 329–350. Springer, 2001.
[33] Mario T. Schlosser, Tyson E. Condie, and Sepandar D. Kamvar. Simulating a file-sharing
p2p network. In Proceedings of the First Workshop on Semantics in P2P and Grid Computing,
2002.
[34] K. Sripanidkulchai, B. Maggs, and H. Zhang. Efficient content location using interest-based
locality in peer-to-peer systems. Proceedings IEEE INFOCOM 2003, pages 342–351, 2003.
[35] Ion Stoica, Robert Morris, David R. Karger, M. Frans Kaashoek, and Hari Balakrishnan.
Chord: A scalable peer-to-peer lookup service for internet applications. In SIGCOMM,
pages 149–160, 2001.
[36] Peter Triantafillou, Chryssani Xiruhaki, and Manolis Koubarakis. Efficient massive sharing
of content among peers. In ICDCS Workshops, pages 681–685. IEEE Computer Society,
2002.
[37] Yamini Upadrashta, Julita Vassileva, and Winfried K. Grassmann. Social networks in peerto-
peer systems. In HICSS. IEEE Computer Society, 2005.
[38] Jean G. Vaucher, Gilbert Babin, Peter G. Kropf, and Thierry Jouve. Experimenting with
gnutella communities. In Distributed Communities on theWeb, 4th InternationalWorkshop,
DCW 2002, Sydney, Australia, April 3-5, 2002, Revised Papers, pages 84–99, 2002.
[39] Xiaoyu Wang, Wee Siong Ng, Beng Chin Ooi, Kian-Lee Tan, and Aoying Zhou. Buddyweb:
A p2p-based collaborative web caching system. In Enrico Gregori, Ludmila
Cherkasova, Gianpaolo Cugola, Fabio Panzieri, and Gian Pietro Picco, editors, NETWORKING
Workshops, volume 2376 of Lecture Notes in Computer Science, pages 247–251.
Springer, 2002.
[40] D.Watts and S. Strogatz. Collective dynamics of small-world networks. volume 393, pages
440–442, 1998.
[41] Duncan J. Watts. Small worlds: The dynamics of networks between order and randomness.
J. Artificial Societies and Social Simulation, 6(2), 2003.
[42] Duncan J. Watts. Six degrees: The science of a connected age. 2004.
[43] B. Yang and Hector Garcia-Molina. Improving efficiency of peer-to-peer search. In In
Proc. of the 28th Conference on Distributed Computing Systems., July 2002.
[44] Beverly Yang and Hector Garcia-Molina. Comparing hybrid peer-to-peer systems. In Peter
M. G. Apers, Paolo Atzeni, Stefano Ceri, Stefano Paraboschi, Kotagiri Ramamohanarao,
and Richard T. Snodgrass, editors, VLDB, pages 561–570. Morgan Kaufmann, 2001.
[45] Beverly Yang and Hector Garcia-Molina. Efficient search in peer-to-peer networks. In
ICDCS, pages 5–14, 2002.
[46] Beverly Yang and Hector Garcia-Molina. Designing a super-peer network. In Umeshwar
Dayal, Krithi Ramamritham, and T. M. Vijayaraman, editors, ICDE, pages 49–. IEEE Computer
Society, 2003.
[47] Ben Y. Zhao, John Kubiatowicz, and Anthony D. Joseph. Tapestry: a fault-tolerant widearea
application infrastructure. Computer Communication Review, 32(1):81, 2002.