An authorization system for database grid

In a database grid environment, which is composed of highly diverse, widely distributed and autonomously managed database resources, how to control access right to these resources is a meaningful problem to discuss, because it's not only depends on policies in virtual organization, but also depends on policies at database end, we cannot ignore requirements of any of them. Besides this, database is a special resource. Its authorization permission is structured, first it has levels such as DB, table, and column level, and each level has several kind of privileges like delete, update and so on, so it's a great burden to map grid users to permissions directly. Secondly, databases already have sophisticated technologies and products in authorization; we need integrate them to our system. To address these issues, we design and implement an authorization system for database grid. It supports building agreements between virtual organization administrator and database administrator to authorize users collaboratively. It based on XML-formed config file now and can be extended to files in other policy language like Rei or Ponder. As one part of DartGrid project, which has been used to build a database grid for traditional Chinese medicine in China, it satisfies realistic requirements in authorization and is working now.