prTorrent: On establishment of piece rarity in the BitTorrent unchoking algorithm
Suman Deb Roy, Wenjun Zeng · 2009
BitTorrent is an extensively adopted p2p Content Distribution System on the Internet. In spite of its proincentive approach and ease of implementation, recent research has empirically shown BitTorrent to be vulnerable to strategic manipulation by its constituent peers in a swarm. Moreover, Honest Piece Revelation and Free-Riding is becoming an increasing concern. Our findings indicate that till date, it is the orthogonal treatment of piece rarity and unchoking, that has encouraged strategic manipulation enabling unfair maximization of incentives in p2p systems. In this paper, we propose that solution to such concerns lies in unifying a Piece Rarity factor with the BitTorrent Unchoking Algorithm. We also discuss a new Discount Parameter attack that compromises most Tit-for-Tat mechanisms. Our analysis demonstrates how underreporting, as a Piece Revelation Strategy in auction based choking algorithms, could result in Starvation. prTorrent, a novel approach based on BitTorrent shows how strategic formulation of the Piece Rarity parameter can optimize incentives in a swarm, and help its constituent peers in achieving the equilibrium facilitating truly co-operative behavior.