EbitSim: An Enhanced BitTorrent Simulation Using OMNeT++ 4

The BitTorrent protocol is one of the most successful P2P applications, being largely studied by the research community. Nevertheless, studying the dynamics of a large BitTorrent network presents several challenges, such as difficulty in acquiring network traces or building measurement experiments. Evaluation through simulation is usually utilized for studying BitTorrent networks, yet only a few BitTorrent simulation models are available for the research community. In this article, we present an extensible framework for developing BitTorrent simulations, focusing on realism and without losing on scalability. We developed an accurate version of the protocol by analyzing the source code of mainstream BitTorrent clients and by discussing directly with their developers. The simulation model was developed with the OMNeT++ Framework, inheriting its high extensibility, and with the INET Framework, for accuracy of the underlying network model. We also took into account the effects of multitasking in our model, since BitTorrent applications acquires content from several sources simultaneously, and utilized real world traces for modeling the processing times. We present an analysis of our simulator regarding performance aspects and BitTorrent-related results.