Software architecture for the UARC Web-based collaboratory

The Upper Atmospheric Research Collaboratory was actively used over a period of six years to study space weather phenomena such as magnetic storms and solar winds. The UARC software was designed as a modular system of independent services that work over a wide area network and support a complex array of data suppliers, transformation modules that provided quality-of-service support, and client tools such as groupware applications. During the last two years of the project, the system provided access to over 30 data sources including ground- and satellite-based instruments and predictive model output from supercomputers during active data collection periods that lasted up to 2 weeks. This article describes the UARC architecture and services. The main UARC servers are a data dissemination substrate specifically designed to support push-based applications using attribute-based routing, and a group management and shared state management server. The servers are scalable, and designed to operate satisfactorily on a wide variety of networking conditions and client resources