The SDSC Storage Resource Broker (SRB) is client-server middle ware that provides a uniform interface for connecting to heterogeneous data resources over a network and accessing replicated data sets. Metadata support in SRB provides a way to access data sets and resources based on their attributes rather than their names or physical locations.
More information about it can be found at the official SRB site
For users of resources of ARCS services, three features of SRB are of particular interest:
support for meta data
the possibility to use SRB for data staging (in and out) from grid compute jobs
fine levels of access control
SRB is being used as the primary means of storing and accessing data with in the ARCS Data Fabric