Trust Policies for Semantic Web Repositories

The increasing reliance on information gathered from the Web and other Internet technologies (P2P networks, e-mails, blogs, wikis, etc.) raises the issue of trust. Trust policies are needed to filter out untrustworthy information. This filtering task can be leveraged by the increasing availability of Semantic Web metadata that describes the information retrieved. It is necessary, however, to adequately model the concept of trustworthiness; otherwise one may end up with operational trust measures that lack a clear meaning. It is also important to have a path from one’s trust requirements to concrete trust policies through Semantic Web technologies. This paper proposes a horn logic model for trust policies, grounded on a real-world model of trust that offers justification for trust decisions and controlled trust measurement. We also propose the use of this model to enhance existing Semantic Web repositories with a trust layer.