|| The cooperative association for Internet data analysis (CAIDA), “ Internet traffic classification,” online available: http://www.caida.org/research/traffic-analysis /classification-overview/, 2009.|
 S. Androutsellis-Theotokis, and D. Spinellis, “A survey of peer-to-peer content distribution technologies,” ACM Computing Surveys, vol. 36, no. 4, pp. 335-371, 2004.
 Napster Inc., Napster Website, http://home.napster.com/.
 I. Stoica, R. Morris, D. Karger, M. F. Kaashoek, and H. Balakrishnan, “Chord: A scalable peer-to-peer lookup service for internet applications,” in Proceedings of SIGCOMM, pp. 149–160, San Diego, CA, Aug 2001.
 A. Rowstron and P. Druschel, "Pastry: Scalable, distributed object location and routing for large-scale peer-to-peer systems," in Proc. Middleware 2001, Germany, November 2001.
 B.Y. Zhao, H. Ling, J. Stribling, S.C. Rhea, A.D. Joseph, and J.D. Kubiatowicz, “Tapestry: A Resilient Global-Scale Overlay for Service Deployment,” in IEEE J. Selected Areas in Comm., vol. 22, no. 1, pp. 41-53, 2004.
 “Gnutella,” http://www.gnutella.com.
 W. Acosta and S. Chandra, “Understanding the practical limits of the gnutella p2p Systems: An analysis of query terms and object name distributions,” in Proceedings of the ACM/SPIE Multimedia Computing and Networking (MMCN’ 08), San Jose, CA, April 2008.
 “The phex gnutella client.” http://phex.kouk.de.
 X. Li and J. Wu. “Searching techniques in peer-to-peer networks,” J. Wu, editor, Handbook of Theoretical and Algorithmic Aspects of Ad Hoc, Sensor, and Peer-to-Peer Networks, Auerbach, New York, USA, 2006.
 J. Mischke and B. Stiller, “A Methodology for the Design of Distributed Search in P2P Middleware,” IEEE Networks, vol. 18, no. 1, Jan-Feb, 2004.
 S. Ratnasamy, P. Francis, M. Handley, R. Karp, and S. Shenker, “A scalable content addressable network,” in Proceedings of the ACM SIGCOMM’01, 161–172, 2001.
 A. Crespo and H. Garcia-Molina, “Routing Indices For Peer-to-Peer Systems,” in Proc. of Int. Conf. on Distributed Computing Systems, Vienna, Austria, 2002.
 V. Kalogeraki, D. Gunopulos, and D. Zeinalipour-yazti, “A local search mechanism for peer-to-peer networks,” in Proc. of the 11th ACM Conference on Information and Knowledge Management (CIKM’02), 2002.
 S. Ciraci, I. Korpeoglu, and O. Ulusoy, “Reducing query overhead through route learning in unstructured peer-to-peer network,” Journal of Network and Computer Applications, vol.32, pp.550-567, 2008.
 S. Voulgaris, A.M. Kermarrec, L. Massoulie, and M. van Steen, “Exploiting semantic proximity in p2p content searching,” in Proceedings of the 10th International Workshop on Future Trends in Distributed Computing Systems, China, 2004.
 ND Doulamis, PN Karamolegkos, A Doulamis, and I Nikolakopoulos, “Exploiting semantic proximities for content search over p2p networks,” Computer Communications, v.32 n.5, pp.814-827, March, 2009
 R. Siebes and S. Kotoulas, “pRoute: Peer selection using shared term similarity matrices,” Journal of Web Intelligence and Agent Systems, vol.5, no.1, pp.89–107, 2007.
 E. Cohen, A. Fiat, and H. Kaplan, “Associative Search in Peer-to-Peer Networks: Harnessing Latent Semantics,” in Proc. IEEE INFOCOM, 2003.
 D. Tsoumakos, and N. Roussopoulos, “Adaptive probabilistic search in peer-to-peer networks,” in Proc. of the 2nd International Workshop on Peer-to-Peer Systems (IPTPS’03), 2003.
 G. Salton, “Automatic Text Processing”, Addison-Wesley Publishing Company, 1989.