To support a diverse array of processing services, brokers and mediators are required. Brokers and mediators support such functions as access to disparate information sources, conversion of incompatible data formats and sophisticated search and data presentation algorithms. Choosing an ORB requires a thourough understanding of an applications present and future software requirements as well as how candidate ORB solutions satisfy these needs. This analysis is usually performed at the software architecture level. After development of this understanding, an informed decision can be made.
Scenarios fall into two categories, direct scenarios and indirect scenrarios.
Direct scenarios are those that can be supported without changing the architecture. Indirect scenarios require the changing of 1 or more components of the architecture. Describe the candiate architectures, capturing the data components and connections. Describe in a notation that is acceptable to all parties. Perform scenario evaluation.