A Semi-Automatic Framework for the Design of Rational Resilient Collaborative Systems

Abstract—Collaborative systems (e.g., P2P instant messaging, file sharing, live streaming applications) constitute the largest traffic of today’s Internet. Common to all these systems is the assumption that, in return to the service offered by the collaborative system, users are willing to participate by sharing their resources with others. However, in practice, these systems suffer from rational users, i.e. users that benefit from the system without contributing their fair share to it. A number of solutions have been devised in the literature to deal with the problem of rational users in collaborative systems. However, most of these solutions are tailored to specific systems and thus lack flexibility and re-usability. In this paper, we propose RACOON, the first framework for RAtional resilient COllabOrative system desigN. RACOON relies on an extensible model that allows a system designer to specify the protocol steps and the different types of rational users he wants to consider. Furthermore, RACOON relies on game theory to reason on the behaviour of rational users. Finally, RACOON includes a simulation module that allows performance-oriented tuning of the system. Throughout the paper, we show how we used RACOON for the design of a rational-resilient, collaborative live-streaming application. Performance evaluation realised on one hundred real machines shows that the configuration proposed by RACOON allows all users to visualise a quality stream even in presence of rational users. I