Classification and Implementations of Workflow-Oriented Grid Portals, To appear

Abstract. Although several grid projects have the aim to develop portals that hide the complexity of distributed computing infrastructures, only few of these portals support workflow-based applications. The number of portals that enable collaborative workflow development or collaborative resource access is even lower. The paper introduces a model to categorize workflow-oriented grid portals based on two general features: ability to access multiple grids simultaneously and support for collaborative problem solving. The generic features of the different categories are discussed and the Globus-based implementations of the various categories are demonstrated by the P-GRADE Portal