QRP07-3: Analyzing the Performance and Fairness of BitTorrent-like Networks Using a General Fluid Model

In this paper, a general fluid model is developed to study the performance and fairness of BitTorrent-like networks. The fluid model incorporates two important features, user settings with multiple groups and inter-group data exchange, in a synthesized way to obtain statistics about the system performance. Our numerical results point out some key parameters of the system, such as the staying time of seeders. Generally, selfish behavior does not receive equal performance degradation, and in some scenarios users have strong incentives of free-riding. We also find content delivery can be greatly deterred when malicious free-riders are overwhelming.