A Computational Web Portal for the Distributed Marine Environment Forecast System

Abstract

This paper describes a prototype computational Web Portal for the Distributed Marine Environment Forecast System (DMEFS). DMEFS is a research framework to develop and operate validated Climate-Weather-Ocean models. The DMEFS portal is implemented as a multitier system. The Web Browser based front-end allows for visual composition of complex computational tasks and transition of these tasks for operational use, as well as for analysis of the results. The middle-tier is split into Java Server Pages based Web tier responsible for request processing and dynamic generation of responses, and Enterprise Java Beans based application server. The EJB container is populated by a hierarchy of entity beans representing the state of the system or acting as proxies of services rendered by the back end. Operations on the entity beans are implemented as session beans. This design makes it possible to separate user requests (in terms of application independent task specification) from the back end resource allocation (through platform independent resource specification). The middle-tier provides a transparent mapping between task and resource specification, hiding complexity of the heterogeneous back-end system from the user. The DMEFS portal provides a seamless and secure access to the computational resources as well as provides a simpler and easy to use interface to setup, stage, and deploy complex scientific and engineering simulations.