Methods for Reliability Evaluation of Trust and Reputation Systems

Trust and reputation systems are a systematic approach to build security on the basis of observations of node’s behaviour. Exchange of node’s opinions about other nodes is very useful to indicate nodes which act selfishly or maliciously. The idea behind trust and reputation systems gets significance because of the fact that conventional security measures (based on cryptography) are often not sufficient. Trust and reputation systems can be used in various types of networks such as WSN, MANET, P2P and also in e-commerce applications.
Trust and reputation systems give not only benefits but also could be a thread itself. Many attacks aim at trust and reputation systems exist, but still such attacks have not gain enough attention of research teams. Moreover joint effect of many of known attacks has been determined as a very interesting field of research. Lack of an acknowledged methodology of evaluation of trust and reputation system is a serious problem. This work aims at presenting various approaches of evaluation such systems. This work also contains a formal description of generalization of many trust and reputation systems which can be used to evaluate reliability of such systems in the context of preventing various attacks.