What does the SRB do?
As the name implies the Storage Resource Broker, brokers storage resources (sorry, couldn't resist). It provides access, via a uniform API, to various types of data storage across local and wide-area networks, and maintains meta-data (data about the data) about each stored object (files). SRB, in conjunction with MCAT, provides a means for accessing data objects and resources through querying their attributes instead of knowing their physical names and/or locations.
The SDSC Storage Resource Broker (SRB) provides the abstraction mechanisms needed to implement data grids, digital libraries, and persistent archives for data sharing, data publication, and data preservation.
Many people, using only a subset of the features, find that using the SRB as global file system is its most compelling function. Users of multiple distributed computing systems find it to be an essential tool to easily and quickly access files from various locations. With the SRB's parallel I/O capabilities, the SRB will transfer files at least as quickly as any other mechanism, and usually faster.
What is zoneSRB? or How can I federate SRB systems?
ZoneSRB (or federated MCAT SRB) is the next generation of the SRB released as Version 3.0. It provides facilties for two or more independent SRB systems to interact with each other and allow for seamless access of data and metadata across these SRB systems. These systems are called the 'zones. More information about zoneSRB can be found at: FedMcat.html and README.zones.