, Volume 98, Issue 6, pp 567–582 | Cite as

Empirical investigation of BitTorrent community graphs



Most of the users of a BitTorrent community participate in multiple swarms, usually simultaneously as uploader and downloader. Thus the inter-swarm aspect of the bandwidth resource allocation has high relevance in the algorithm design of deployed BitTorrent clients. This inter-swarm connections among the users of a BitTorrent community can be represented by a flow network of special structure. Using this representation it has been demonstrated that de facto solutions to the resource allocation in BitTorrent communities are suboptimal. In this paper we investigate this conclusion in more details using graph measures and optimization techniques. We find that BitTorrent communities are sensitive for removal of highly contributing users, that the inter-swarm connectivity can lead to different performance results, and that torrent selection mechanisms can hardly improve the average download performance of users. Regarding the theoretical optimum of the discussed problem we show that it does not necessary comply with the BitTorrent protocol.


BitTorrent Private communities Resource allocation Flow networks Network science 

Mathematics Subject Classification

68M14 90C35 05C21 



This work was partially supported by the European Union and the European Social Fund through project (Grant No.: TAMOP-4.2.2. C-11/1/KONV-2012-0013). T. Vinkó was supported by the Bolyai Scholarship of the Hungarian Academy of Sciences.


  1. 1.
    Wierzbicki A (2010) Trust and fairness in open. In: Distributed systems, vol 298. Springer, BerlinGoogle Scholar
  2. 2.
    Lan T, Kao D, Chiang M, Sabharwal A (2010) An axiomatic theory of fairness in network resource allocation. In: Proceedings of the IEEE INFOCOM, 2010, pp 1–9Google Scholar
  3. 3.
    Cohen B (2003) Incentives build robustness in BitTorrent. In: Workshop on economics of peer-to-peer systems, vol 6, pp 68–72Google Scholar
  4. 4.
    Chen X, Jiang Y, Chu X (2010) Measurements, analysis and modeling of private trackers. In: IEEE tenth international conference on peer-to-peer computing (P2P), pp 1–10Google Scholar
  5. 5.
    Liu Z, Dhungel P, Wu D, Zhang C, Ross K (2010) Understanding and improving ratio incentives in private communities. In: IEEE 30th international conference on distributed computing systems (ICDCS), pp 610–621Google Scholar
  6. 6.
    Rahman R, Meulpolder M, Hales D, Pouwelse J, Epema D, Sips H (2010) Improving efficiency and fairness in p2p systems with effort-based incentives. In: IEEE international conference on communications (ICC), pp 1–5Google Scholar
  7. 7.
    Vinkó T, Santos F, Andrade N, Capotă M (2013) On swarm-level resource allocation in BitTorrent communities. Optim Lett 7:923–932MathSciNetCrossRefMATHGoogle Scholar
  8. 8.
    Capotă M, Andrade N, Vinkó T, Santos F, Pouwelse J, Epema D (2011) Inter-swarm resource allocation in BitTorrent communities. In: IEEE international conference on peer-to-peer computing (P2P), pp 300–309Google Scholar
  9. 9.
    Ford LR, Fulkerson DR (1956) Maximal flow through a network. Can J Math 8:399–404MathSciNetCrossRefMATHGoogle Scholar
  10. 10.
    Goldberg AV, Tarjan RE (1988) A new approach to the maximum-flow problem. J ACM 35(4):921–940MathSciNetCrossRefMATHGoogle Scholar
  11. 11.
    Andrade N, Santos-Neto E, Brasileiro F, Ripeanu M (2009) Resource demand and supply in BitTorrent content-sharing communities. Comput Netw 53(4):515–527CrossRefMATHGoogle Scholar
  12. 12.
    Roozenburg J (2006) Secure decentralized swarm discovery in Tribler. Master’s thesis, Delft University of Technology (2006)Google Scholar
  13. 13.
    Isdal T, Piatek M, Krishnamurthy A, Anderson T (2007) Leveraging bittorrent for end host measurements. In: Uhlig S, Papagiannaki K, Bonaventure O (eds) Passive and active network measurement, vol 4427., Lecture notes in computer scienceSpringer, Berlin, pp 32–41CrossRefGoogle Scholar
  14. 14.
    Amaral LAN, Scala A, Barthelemy M, Stanley HE (2000) Classes of small-world networks. Proc Natl Acad Sci 97(21):11149–11152CrossRefGoogle Scholar
  15. 15.
    Caldarelli G (2007) Scale-free networks: complex webs in nature and technology. Oxford University Press, OxfordGoogle Scholar
  16. 16.
    Onnela J-P, Saramäki J, Hyvönen J, Szabó G, Lazer D, Kaski K, Kertész J, Barabási A-L (2007) Structure and tie strengths in mobile communication networks. Proc Natl Acad Sci 104(18):7332–7336CrossRefGoogle Scholar
  17. 17.
    Chu X, Chen X, Jia A, Pouwelse J, Epema D (2014) Dissecting darknets: measurement and performance analysis. ACM Trans Internet Technol 13:125CrossRefGoogle Scholar
  18. 18.
    Kash IA, Lai JK, Zhang H, Zohar A (2012) Economics of BitTorrent communities. In: Proceedings of the 21st international conference on World Wide Web. ACM, New York, pp 221–230Google Scholar
  19. 19.
    Cuevas R, Kryczka M, Cuevas A, Kaune S, Guerrero C, Rejaie R (2010) Is content publishing in BitTorrent altruistic or profit-driven? In: Proceedings of the 6th international conference, Co-NEXT 10. ACM, New York, pp 1–12Google Scholar
  20. 20.
    Meng X, Tsang P-S, Lui K-S (2013) Analysis of distribution time of multiple files in a P2P network. Comput Netw 57(15):2900–2915CrossRefGoogle Scholar
  21. 21.
    Liang C, Zhao M, Liu Y (2011) Optimal bandwidth sharing in multiswarm multiparty p2p video-conferencing systems. IEEE/ACM Trans Netw 19(6):1704–1716CrossRefGoogle Scholar
  22. 22.
    Peterson RS, Sirer EG (2009) Antfarm: efficient content distribution with managed swarms. In: NSDIGoogle Scholar
  23. 23.
    Dunn RJ, Gribble SD, Levy HM (2007) The importance of history in a media delivery system. In: IPTPSGoogle Scholar
  24. 24.
    Zhong L, Wang X, Kihl M (2011) Topological model and analysis of the P2PBitTorrent protocol. In: 9th World Congress on Intelligent Control and Automation (WCICA), pp 753–758Google Scholar
  25. 25.
    Delaviz R, Zeilemaker N, Pouwelse JA, Epema DHJ (2013) A network science perspective of a distributed reputation mechanism. In: IFIP networking, pp 1–9Google Scholar
  26. 26.
    Hu C, Shan D, Cheng Y, Qin T (2013) Inter-swarm content distribution among private bittorrent networks. IEEE J Sel Areas Commun 31(9-Supplement):132–141Google Scholar

Copyright information

© Springer-Verlag Wien 2015

Authors and Affiliations

  1. 1.Institute of InformaticsUniversity of SzegedSzegedHungary

Personalised recommendations