A Comprehensive Comparison of Trust Management Systems for Federation

Federation becomes pervasive in information sharing and collaborations over distributed systems, ubiquitous systems, and the Internet. Trust management plays a critical role to smooth collaborations and information sharing across different trust domains. The federation of trust management is a new direction for these networked systems. In this paper, the requirements and a set of evaluation metrics for federated trust management systems are briefly examined, and then a comprehensive comparison of extant trust management systems is made against these metrics. The purpose of this paper is not to provide an ultimate comparison covering all necessary features; instead, its purpose is to initiate a discussion and to offer a context in which to evaluate current and future solutions, in order to encourage the development of proper models and systems for federated trust management.