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Depending on the "flavor" of the configuration, use patterns, and policies, the SRB creates what is called a data grid, a digital library, persistant archive, and/or distributed file system.
SRB provides a uniform interface to heterogeneous data storage resources over a network. As part of this, it implements a logical namespace (distinct from physical file names) and maintains metadata on data-objects (files), users, groups, resources, collections, and other items in an SRB Metadata Catalog (MCAT) stored in a relational database management system. System and user-defined metadata can be queried to locate files based on attributes as well as by name. SRB runs on various versions of Unix, Linux, and Microsoft Windows.
The SDSC SRB system is middleware in the sense that it is built on top of other major software packages (various storage systems, real-time data sources, a relational database management system, etc) and it has callable library functions that can be utilized by higher level software. However, it is more complete than many middleware software systems as it implements a comprehensive distributed data management environment, including various end-user client applications. It has features to support the management and collaborative (and controlled) sharing, publication, replication, transfer, and preservation of distributed data collections.
SDSC SRB is sometimes used in conjunction with computational grid computing systems, such as Globus Alliance, and can utilize the Globus Alliance Grid Security Infrastructure (GSI) authenticationIn computer security, authentication is the process by which a computer, computer program, or another user attempts to confirm that the computer, computer program, or user from whom the second party has received some communication is, or is not, the claim system.
SRB can store and retrieve data in archival storage systems such as HPSS and SAM-FS, on disk file systems (Unix, Linux, or Windows), as Binary Large Objects or tabular data in relational database management systems, and on tape libraries.
The SRB has been used in production since 1997 and at SDSC is currently (late 2004) managing over 300 terabyteA terabyte is a unit of measurement in computers. Because of irregularities in definition and usage of the kilobyte, the exact number of bytes in a terabyte in common practice could be either of the following values: # 1,000,000,000,000 bytes 1012. This ds of data in over 50 million files. Many other computer centers and consortia are independently managing additional SRB data collections.
While licensed, SRB source distributions are freely available to academic and non-profit organizations. A commercial version (which diverged from the SDSC version in 2001) is also available.