1 Is Content Publishing in BitTorrent Altruistic or Profit-Driven? 梁懿

2 Outline ★ Measurement Methodology ★ Analysis of Collective Data ★ Incentives of Major Publishers 1

3 Question What are the main incentives of major content publishers in BitTorrent? 2

4 How a user joins a BitTorrent swarm?.torrent file -> tracker -> number of seeders + random IP address of peers (50) 3

5 Two BitTorrent Portals: Mininova, Pirate Bay 4

6 Measurement methodology Identifying Initial Publisher: Username: portal IP address:.torrent file (newest -> peers least) MaxMind Database: publisher IP address, downloader IP address, ISP, geography location. 5

7 Dataset Description 6

8 Skewness of Contribution 3% publishers contribute 40% resources In pb10 dataset, 40% top100 publishers no download, 80% download less than 5 files 7

9 Wonder Significant amount of processing and bandwidth + Legal implications Why this small fraction of publishers allocate a great deal of resources into BitTorrent swarms? 8

10 OVH(hosting provider): Paying for a well provisioned service to publish a much larger number of files, to some commercial users who buy big amount of solid bw. Comcast(commercial ISP): Altruisticly publish a small number of files from their home or work, to some common users, such as ADSL. ISP Distribution 9

11 Content Type 10 Pb10

12 Top is 7 times of All, Top-HP is 1.5 times of Top-CI Average Downloaders Number 11

13 Seeding Behavior 12 Average Seeding Time per Content

14 3 Types of Publishers  Fake Publishers: fake nature -> torrents unpopular -> seed all torrents + long time  Financial Publishers: relative long time torrents -> attract more users to download  Altruistic Publishers : publish + consume 13

15 Incentives of Fake Publishers  Antipiracy Agents: publish fake versions of copyrighted content.  Malicious Publishers: lead users to download a malware. 14

16 Incentives of Financial Publishers Private BitTorren Traker:  Posting advertisement in their web sites  Require a fee for VIP access that allows the client to download more contents. 15

17 16

18 17

19 18

20 Incentives of Financial Publishers 19

21 Incentives of Altruistic Publishers  Publish small music and e-book files that require small amount of seeding resources.  Extensive description of the content.  Often ask other users to help with seeding the content. 20

22 3%publisher: 67% content 79% downloads Fake: 30% content, 25%download others: 37% content, 54%download Will BitTorrent survive as the most popular file-sharing application without these publishers? 21

23 THANKS!