Detecting the P2P swarm

analyzing their distribution is a challenging task

which has not received the deserved attention.We used active measurement methodology to continuously trace the real-world BitTorrent swarms over the Internet from a stub network for a long period of time.Our measurements achieved the ability of real-time scanning the online peers

avoiding the potential copyright infringement and heavy traffic on Internet.During the over eight-month measurements

from July 15 2010 to March 31 2011

we crawled 33

008 swarms

collected 8

963

776 distinct peers.Then we analyzed the distributions and preferences of peers.We find that the geographical distribution of peers in all swarms span quite universally.And there are some quite differences in the preferences between the users in and outside China.