Junwei Cao is a research scientist of the MIT LIGO Laboratory. His research is focused on distributed and grid computing. He is currently working on the LIGO Scientific Collaboration (LSC) Data Grid to enable gravitational wave physics applications. He is a member of the LSC Data Analysis Software Committee and the Open Science Grid Consortium.

Before joining MIT in July 2004, Junwei Cao was a research staff member of C&C Research Laboratories, NEC Europe Ltd., Germany. He completed his PhD in Computer Science at the University of Warwick, U.K. in 2001, MS and BS at Tsinghua University, China in 1998 and 1996, respectively. He is an IEEE Senior member and ACM member.

The LIGO (Laser Interferometer Gravitational-wave Observatory) project aims to make the first direct detection of gravitational waves as predicted by Einstein's General Theory of Relativity. The project is a joint enterprise of the California Institute of Technology and Massachusetts Institute of Technology funded by the U.S. National Science Foundation (NSF). LIGO Laboratory consists of facilities at both universities in addition to two observatory sites in the states of Washington and Louisiana.

The LIGO Scientific Collaboration (LSC) consists of over 500 scientists from about 40 institutions. It is leading the international effort on gravitational wave research and is responsible for the analysis of data which the LIGO instruments collect. The LSC Data Grid (LDG) is a production-quality grid computing infrastructure to support LIGO data analysis and monitoring with thousands of CPUs and terabytes of data storage capabilities distributed over ten sites in the USA and Europe.

This talk provides a brief introduction to the LDG client/server environment, the LDG middleware to create a coherent and uniform LIGO data analysis environment for LSC members. The environment is built on top of the Virtual Data Toolkit (VDT) that provides general purpose grid tools (e.g. Globus and Condor). Two LSC applications are also described in this talk, which are built on top of the LDG client/server environment. The LIGO Data Monitoring (LDM) environment is developed to enable offline LIGO data analysis applications implemented using the LIGO Data Monitoring Toolkit (DMT). The LDG report is a small utility that queries each LDG clusters for usage statistics, coupled with LSC user information, to generate annual usage report of LDG resources automatically. These applications interface users with a LIGO friendly language and hide technical details of grid computing from users.