Mundinger, JochenLe Boudec, Jean-Yves2006-08-252006-08-252006-08-252006https://infoscience.epfl.ch/handle/20.500.14299/233801The application of decentralized reputation systems is a promising approach to ensure cooperation and fairness, as well as to address random failures and malicious attacks in Mobile Ad-Hoc Networks. However, they are potentially vulnerable to liars. With our work, we provide a first step to analyzing robustness of a reputation system based on a deviation test. Using a mean-field approach to our stochastic process model, we show that liars have no impact unless their number exceeds a certain threshold (phase transition). We give precise formulae for the critical values and thus provide guidelines for an optimal choice of parameters.Mobile Ad-Hoc Networkreputation systemrobustness against liarsmean-field approachperformance optimizationtext::report