Reputation Management in Grid-based Virtual Organisations

Grid computing allows one to access, utilise and manage heterogeneous resources in virtual organisations across multiple domains and institutions. The formation and operation of virtual organisations involve establishing trust among their members and reputation is one measure by which such trust can be quantified and reasoned about. This paper presents a reputation model for Grid-based virtual organisations that can be used to rate users as well as resources and their providers. The model is based on utility computing, which expresses the satisfaction of an entity in its interactions with other entities with respect to some issues of interest. We show how the model can be used to rate users according to their resource usage and resource providers according to the quality of service provided. Finally, we demonstrate through Grid simulations, how the model can be useful in improving completion and welfare in a virtual organisation.