Computer systems in the world are connected via the Internet and accessed by scientists. Often scientists require the simultaneous use of several computer systems for calculations on a very large scale. In addition, they require simultaneous access of databases and files on their systems in order to combine the information. However, it has been very difficult to satisfy these requirements because different computer systems have different software environments such as operating systems and middleware.
A concept of distributed computing over the Internet, termed as GRID or Grid computing, has recently become very popular. Presently, GRID has a very wide range of application in various sciences including high energy physics. Actually, high energy physics led the field of the Data GRID for data intensive computing. Unfortunately, different GRID middleware has been developed in different regions of the world and is hence not compatible with each other. Computing resources at the sites can be accessed only within the same GRID middleware.
A research unit of the Computing Research Center at KEK developed a new software layer that bridges the differences among the various GRID middleware based on the international standard, SAGA. The architecture of the software is shown in Fig. 1. This software technology can be used to access computing resources on systems even when different GRID middleware is used. This can be achieved by a single command syntax that enables submission of jobs and access of files anywhere in the world.
The research unit demonstrated their achievements at the SC2009 conference, which is the biggest computing- related conference. Jobs were simultaneously submitted to the computer system at Louisiana State University (LSU) and KEK, and the calculated results were accumulated to copy the files from both sites. In this demonstration, simulation of particle therapy was performed as an example, as shown in Fig. 2. Several particles were injected in parallel into the human body, and the radiation dose from these particles was accumulated. This simulation was performed using both systems in parallel.
This research is a part of the REsources liNKage for E-scIence (RENKEI) project. RENKEI is a research and development project for new middleware technologies to enable e-science communities. "RENKEI" is Japanese word meaning "federation." The goal of the project is to develop middleware to federate/share resources (computers, storages, databases, and applications) distributed among multiple organizations such as research laboratories, national computer centers, and international GRIDs. Research activities consist of five research themes presented in the project web page. This project is supported by the Ministry of Education, Culture, Sports, Science and Technology, Japan (see http://www.e-sciren.org/).
(from 2009 KEK annual report)