Abstract
P2P file-sharing systems have been suffering from file unavailability or poor download speed due to lack of enough seeds. To download rare files, users are typically forced to keep their desktops online for a long time, which is undesirable for most users. To get over this, several commercial P2P systems launched offline download service, also known as cloud download, which employs stable and high-capacity servers to take over users’ download tasks, and thus users do not need to stay online all the time. This paper focuses on characterizing the performance of offline download, including the overall performance provision and the expected performance of individual download tasks. Through model characterization and experimental verification based on real-world trace, we are the first to confirm the feasibility and effectiveness of offline download for a large spectrum of P2P systems: over 90 % files can be successfully retrieved, and most of the downloads only take a few days. Furthermore, we disclose that the completion time of offline download is extremely volatile, and thus develop a method to accurately predict the expected performance of individual downloads. An instance of applying the prediction results is also presented to save the server-side bandwidth. Finally, we implement a prototype of offline download service, release it in a real P2P network, and present our work experience with it.
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Notes
A file is defined as valid if there exists any replica appears online after the observation time point.
Critical region is a period of time to which the timeout threshold is close.
References
Sandvine (2012) Sandvine global internet phenomena report. Tech. Rep.
Neglia G, Reina G, Zhang H, Towsley D, Venkataramani A, Danaher J (2007) Availability in bittorrent systems. In: INFOCOM ’07
Pucha H, Andersen D, Kaminsky M (2007) Exploiting similarity for multi-source downloads using file handprints. In: NSDI ’07
Kaune S, Rumin R, Tyson G, Mauthe A, Guerrero C, Steinmetz R (2010) Unraveling BitTorrent’s file unavailability: measurements and analysis. In: P2P ’10
Garbacki P, Iosup A, Epema D, van Steen M (2006) 2fast: collaborative downloads in p2p networks. In: P2P ’06
Wang J, Yeo C, Prabhakaran V, Ramchandran K (2007) On the role of helpers in peer-to-peer file download systems: Design, analysis and simulation. In: IPTPS ’07
Sun Y, Liu F, Li B, Li B, Zhang X (2009) Fs2you: peer-assisted semi-persistent online storage at a large scale. In: INFOCOM ’09
Yin H, Liu X, Zhan T, Sekar V, Qiu F, Lin C, Zhang H, Li B (2009) Design and deployment of a hybrid CDN-P2P system for live video streaming: experiences with LiveSky. In: ACM MM ’09
Menasche D, Rocha A, Li B, Towsley D, Venkataramani A (2009) Content availability and bundling in swarming systems. In: CoNEXT ’09
Hlavacs H, Hummel K, Weidlich R, Houyou A, Berl A, De Meer H (2008) Energy efficiency in future home environments: a distributed approach. home networking, pp 69–84
Over 3 billions of offline downloads in thunder. http://act.vip.xunlei.com/lixian_30/
Huang Y, Li Z, Liu G, Dai Y (2011) Cloud download: using cloud utilities to achieve high-quality content distribution for unpopular videos. In: ACM MM
Xu Y, Ao N, Chenm C, Chen Y, Huang Y (2011) User data mining in a large-scale peer-assisted offline download system. In: ICWMMN
Naixiang A, Yingying X, Changjia C, Yuchun G (2012) Offline downloading: a non-traditional cloud-accelerated and peer-assisted content distribution service. In: CyberC
Xing Y, Yang Z, Chen C, Xue J, Dai Y (2011) On the qos of offline download in retrieving peer-side file resource. In: ICPP ’11
Xu D, Kulkarni S, Rosenberg C, Chai H (2006) Analysis of a CDN–P2P hybrid architecture for cost-effective streaming media distribution. Multimedia Systems 11(4):383–399
Tian J, Dai Y (2007) Understanding the dynamic of peer-to-peer systems. In: IPTPS ’07
Yang Z, Dai Y, Xiao Z (2009) Exploring the cost-availability tradeoff in P2P storage systems. In: ICPP ’09
Ross S M (2006) Introduction to probability models, 9th edn. Academic Press
Xunlei prospectus http://www.sec.gov/Archives/edgar/data/1510593/000104746911005752/a2202187zf-1.htm
Menasché D S, de A Rocha A A, de Souza e Silva E A, Towsley D, Meri Leäo R M (2011) Implications of peer selection strategies by publishers on the performance of p2p swarming systems. ACM SIGMETRICS Performance Evaluation Review
Acknowledgments
The authors would like to thank Jinyang Li, Christopher Mitchell from New York University, and the anonymous reviewers of ICPP’ 11 for their valuable comments and suggestions. This work was supported by the National High Technology Research and Development Program (“863” Program) of China (Grant No. 2013AA013203), the National Basic Research Program of China (Grant No. 2011CB302305), and the State Key Program of National Natural Science of China (Grant No. 61232004).
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Yang, Z., Xing, Y., Chen, C. et al. Understanding the performance of offline download in real p2p networks. Peer-to-Peer Netw. Appl. 8, 992–1007 (2015). https://doi.org/10.1007/s12083-014-0305-z
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DOI: https://doi.org/10.1007/s12083-014-0305-z