BitTorrent (BT) has become an extremely popular and successful peer-to-peer (P2P) file sharing system. Although empirical evidence suggests that most nodes participate in multiple torrents, surprisingly little research literature exists on this topic. In this paper, we focus on a multi-torrent system, and specifically on the questions of (a) what incentives could be provided for nodes to contribute resources as seeds in a multi-torrent environment, and (b) what are the resulting performance consequences of such behavior, both on the nodes which are willing to be seeds and on the overall system. We give evidence of the current system lacking incentives for nodes to stay around as seeds in a multi-torrent environment. Motivated by that, we propose a cross torrent based method and then present a simulation-based performance study to illustrate the benefits of our approach.
Yan Yang, Alix L. H. Chow, Leana Golubchik