Systems

Systems of maps are executable units. The Integration Flow Designer enables you to use a system as a component of another system. This type of system is a subsystem component. A system can contain two types of components: map components and subsystem components. A subsystem component is a reference to another system that you have already defined. As with map components, the Integration Flow Designer displays subsystem components graphically.

A system can consist of map components and subsystem components. Subsystems can also be nested within subsystems. The Integration Flow Designer Navigator displays systems and the contained subsystems in a hierarchical and alphabetical list.

A map component and a subsystem component are conceptually similar. The difference between them is that they operate at different layers. As with a map component, a subsystem is an Integration Flow Designer object. A subsystem does the following:

• Encapsulates an executable system and includes a surrounding layer of execution settings used at run time
• Can include a subsystem component with a defined set of interfaces based on the sources and targets of the various maps that it contains

At design time, you decide which subsystem components you want to add to a system. A subsystem component can reference another system you have defined within a system definition file (.msd).

A subsystem component can also reference a design document that you have produced by using a preferred tool (a type is registered with the Windows platform). This facility helps you to keep track of design-related and implementation-related information at a system level.

As with map components, it is important to recognize that while a subsystem references another system, it does not consume it. The system being referenced is reusable. Another subsystem can also reference the same system.

Systems and the subsystems that reference them have execution settings. The execution settings include the server that will execute the system and the type of Command or Launcher that will run the system.

The following table lists some similarities of maps and systems of maps: