Formalising trust for online communities

Provision of services within a virtual framework for resource sharing across institutional boundaries has become an active research area. Many such services encode access to computational and data resources. Consequently, we envision a service rich environment in the future, where service consumers are represented by intelligent agents. If interaction between agents is automated, it is necessary for these agents to be able to automatically choose between a set of equivalent (or similar) services. In such a scenario trust serves as a benchmark to differentiate between services. The concept of trust suffers from an imperfect understanding, a plethora of definitions, and informal use in the literature. We present a formalism for describing trust within multi-institutional service sharing that can be embedded in an artificial agent; enabling the agent to make trust-based decision