Fairness is an important management issue for
peer-to-peer file sharing systems. In this paper, we study the
credit system of the P2P file sharing network eMule
(http://www.emule-project.net) through a simple queueing
network model. Numerical analysis and experimental results
show that this local credit strategy could effectively deal with free
riders and provide fairness for the system during a single file
exchange. Using this model, we also investigate different
management strategies for dealing with the newcomer fairness
issue. We propose a simple, private history-based scheme to
balance the fairness between two types of newcomers.
