OPAL OP: AN EXTENSIBLE GRID-ENABLING WRAPPING TOOL FOR LEGACY APPLICATIONS
This paper describes a new approach (Opal OP: Opal Operation Provider) to wrap existing legacy applications as Grid services. In order to expose, with minimal effort, existing applications as Grid services, Opal OP provides a method for wrapping a legacy application as a program module, or as an operation provider. Traditional wrapping methods usually restrict the way to implement Grid services because these methods provide only a suite of interfaces necessary for using the wrapped application. The proposed Opal OP, on the other hand, doesn't restrict the way to implement a Grid service from a legacy application. Opal OP is imple-mented as an operation provider that wraps the application and thus can be used as a module in the Grid service. Application developers can easily develop their own services where legacy applications are wrapped through the utilization of Opal OP. In this paper, we show some scientific applications including a bio-molecular simulation system developed as Grid services using Opal OP. The results show the usefulness and effectiveness of Opal OP.