A Component based Services Architecture for Building Distributed Applications

| This paper describes an approach to building a distributed software component system for scienti c and engineering applications that is based on representing GRID services as application-level software components. These GRID services provide tools such as registry and directory services, event services, and remote component creation. While a servicesbased architecture for Grids and other distributed systems is not new, this framework provides several unique features. First, the public interfaces to each software component are described as XML documents. This allows many adaptors and user interfaces to be generated from the speci cation dynamically. Second, this system is designed to exploit the resources of existing Grid infrastructures like Globus[7], [15], Legion[17], [7], and commercial Internet frameworks like e-speak[11]. Third, and most important, the component-based design extends throughout the system. Hence tools such as application builders which allow users to select components, start them on remote resources, and connect and execute them, are also interchangeable software components. Consequently, it is possible to build distributed applications using a graphical \drag-and-drop " interface, a webbased interface, a scripting language like Python, or an existing tool such as Matlab.