Costs and benefits of reputation management systems

The specific objective of a reputation management system is to facilitate nodes to decide whom to trust before providing resources and the expected quality of service. In self-organized systems, the use of reputation-based mechanisms has a cost in terms of messages required to disseminate feedbacks and to synchronize reputation values. In this paper we discuss the implementation of a reputation management system and consider two approaches to collect and disseminate data: proactive and reactive schemes. We analyze the cost of these approaches in terms of extra signaling and evaluate the benefit of using reputation management systems, measured as the number of avoided transactions with malicious nodes.