UML Representation: component in the business analysis model, stereotyped as <<business system>>. A
business system is at the same scale as a UML subsystem and, because it is a component, has packaging semantics as
well. The top-level component of the model is the business or part of the business under consideration, and
appears in the context diagram in the Artifact: Business Analysis Model, where its relationship with
the business environment is shown.
Business Systems should be used to manage dependencies within the organization by explicitly defining the capabilities
(or services) that each Business System provides. This implies that the Business System encapsulates its contained
elements so that users of its services do not depend on how it provides its services but rather on what
services it provides.
This rule can be relaxed when encapsulation is not important. In this case, Business Systems may directly interact
with, or be dependent on elements contained within other Business Systems. Formally specifying in detail the notional
services that must be provided at the Business System boundary is less important in this case because ultimately
those services belong with the elements contained in the Business System, and it is to services on those contained
elements that a service user will bind. This variation regards the Business System more as a packaging
(structuring) mechanism, rather than as a concept in itself.
When this is done, the business system essentially does not exist at execution time, that is, as the business operates,
because its notional services are provided directly by its contained elements. Even so, it may still indicate a real
business organizational boundary, with ownership of resources.