Public and private BitTorrent communities:A measurement study

M. Meulpolder, L. D’Acunto, M. Capotă, M. Wojciechowski, J.A. Pouwelse, D.H.J. Epema, H.J. Sips

TU Delft

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Contents

BitTorrent communities

Goal

Experimental setup

Measurement results

Conclusions

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BitTorrent communities

Content discovery web pages

Communities

User accounts

Comments

Ratings

Forums

Public and private

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Motivation and goal

Private communities employ more incentives

Are there differences between public and private?

Download speed

Connectability

Seeding duration

Seeder/leecher ratio

Fraction of bytes from seeders

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Experimental setup

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Measurement details

Time - September to December 2009

508 269 users

444 swarms

Over 20 million bitfields

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Download speed

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Download speed

Vs. previous results

Guo, IMC 2005, public

160 kbit/s meanPouwelse, IPTPS 2005, public

240 kbit/s mean4 x higher overall mean36 x higher PolishTracker mean

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Connectability

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Connectability

Vs. previous results

Pouwelse, IPTPS 2005

40% overall, same as today2 x lower PolishTracker meanMol, P2P 2008

66% for ThePirateBay45% for TVTorrents

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Seeders and leechers

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Seeding duration

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Seeding duration

Previous results

Pouwelse, IPTPS 2005

83% < 1 hGuo, IMC 2005

8% > 1 day

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Source of incoming bytes

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Conclusions

Private vs. public

Speed is 3-5 times faster

Percentage of unconnectable peers is 1/2

Seeder/leecher ratio is at least 10 times higher

Seeding duration is much longer

The tit-for-tat mechanism is much less important