The Enterprise Component Pattern below shows the service component acting as a facade for the underlying functional and
technical components. Services are exposed on the edge of the service component at the component facade. Requests for
services on the facade are forwarded to a mediator which then routes the message to the appropriate functional or
technical component.
Figure 1. Sample rendering of the Enterprise Component pattern
The dependencies and needs of the functional components to the technical components, for the Rent-a-car example, are
depicted in Figure 2.
Figure 2. Rent-a-car reservation service using the enterprise component pattern
The collection of subsystem component models is gathered into the functional component model which shows the reliance
of the functional components on the technical components, and the inter-relationships between the functional components
themselves. Leaf-level sub-processes that are assigned to the subsystem facade need to be specified as services the
subsystem will provide. These sub-processes are supported and implemented through a finer grained set of system use
cases encapsulated within the structure of the subsystem. The functional components are relied upon for the realization
of the use cases. In turn the functional components depend on the technical components and utilities for their
infrastructure needs.
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