"Grid2003 is not a fancy grid," said Fermilab Computing Division Head Vicky White, "It is only a first step, but it does what a computer grid is supposed to do for scientific research. It successfully combines computing power from multiple sources and transports data to and from offsite locations to allow individual scientists to solve scientific problems at their desktop computers."

Grid2003 is a pilot for the U.S. Open Science Grid, proposed to operate at a much larger scale with more resources from more organizations and with more sophisticated services. The Open Science Grid will federate with other grids now under development around the world to create a global data grid for science. For example, the worldwide particle physics collaborations, ATLAS and CMS, will rely on grid computing for experiments at the Large Hadron Collider, under construction at CERN, the European Particle Physics Laboratory in Geneva, Switzerland,. The Open Science Grid will "interoperate" with the LHC Computing Grid in Europe, and others, to provide a global grid that LHC experimenters around the world will use to transport and analyze the huge volumes of data from the experiments.

Physicist Paul Avery, Professor of Physics from University of Florida, Gainesville, called Grid2003 a significant advance in the use of grid computing for science.

"Grid2003 extends the scale of previous grid demonstrations in terms of the number of sites and robustness of the system," Avery said.

Computer scientist Ian Foster, of the Department of Energy's Argonne National Laboratory and the University of Chicago, is leader of the Globus Alliance, an organization devoted to the development of common worldwide standards for global grid computing.

"The mix of applications from experimental science and computer science research running on Grid2003 shows that our underlying grid protocols are increasingly robust and flexible," Foster said.

"Testing the interoperability of Grid2003 and the LHC Computing Grid in Europe for the movement of data and distribution of computations gives us increased confidence in the general applicability and usability of our infrastructure for the future of global grid computing," said CERN computer scientist Ian Bird.

Scientists demonstrated Grid2003, which has been operating since September, during last month's Supercomputing 2003 Conference in Phoenix. During the five-day demonstration, Grid2003 combined computing resources from its member organizations to make up to 2700 CPUs available to users. For comparison, a typical desktop computer has about 2 CPUs.

During last month's demonstration, scientists from the CMS and ATLAS particle physics experiments used Grid2003 to perform simulations of particle collision events, a critical step for comparison to the real collisions that will begin later in the decade. Astrophysicists from the Sloan Digital Sky Survey, a project to create world's most comprehensive map of the sky, used Grid2003 to perform data analysis. Collaborators of the proposed BTeV experiment at Fermilab also used Grid2003 for particle event simulations. Experimenters of LIGO, the Laser Interferometer Gravitational Wave Observatory did an analysis searching for continuous gravitational wave signals. Two biology applications, a bio-molecular analysis based on "shake and bake" technology and a protein sequence analysis, were performed at short notice on Grid2003.

"We are especially pleased that scientists from a number of different fields used Grid2003 in this first application of the grid for multiple experiments," said U.S. ATLAS physicist Robert Gardner of the University of Chicago. With Ruth Pordes, a Fermilab computer scientist, Gardner serves as Grid2003 coordinator.

"Grid2003 concentrates on the use of a common set of simple, low-level services by many different user groups," Pordes said. "It handles and prioritizes the requests for running the applications on the many different systems. It also monitors various parameters such as which services are available for use and how many organizations are using resources at a given time."

You can monitor the current state of Grid2003 at http://gocmon.uits.iupui.edu/ganglia-webfrontend/

Grid2003 provided invaluable real-world experience in grid computing, said computer scientist Miron Livny of the University of Wisconsin.

"Grid2003 has shown scientists the potential benefits of sharing their distributed sets of computers," Livny said.

Although the initial demonstration is complete, U.S. CMS scientist Ian Fisk said that physicists are continuing to use Grid2003 for particle event simulations.

"Using this shared infrastructure is proving that with care it can be as efficient and convenient as using our own computers, Fisk said.

To use Grid2003, a scientist must belong to one of the member organizations that provide computing capacity. Each user must register through an authentication system to receive a "grid certificate," which works like a passport to identify users.

Each Grid2003 member site presents a common interface to users. The use of common standards in grid development is an important factor in determining future compatibility and interoperability among the world's data grids. Scientists used common technologies from the Virtual Data Toolkit, which includes the Condor and Globus Toolkits, as well as software developed by the European Data Grid and the participating science organizations, to build Grid2003

Some 30 scientists from member universities and laboratories collaborated on the development of Grid2003. The Department of Energy's Office of Science, the National Science Foundation and the member universities provided funding for the project.