Model Parts, Diagrams, Dictionary Items, and Properties > Dictionary items > Subsystem (dictionary item)
  
Subsystem (dictionary item)
For automation interface information about a Subsystem, see Subsystem (automation interface).
A Subsystem contains components providing a common service. It has a boundary to which items can connect.
You can create a System through the context menu of a Package: right-click the Package, point to New, point to Proprietary, point to System Architecture Model, and then click Subsystem. You can also create a Subsystem through a System Architecture Diagram or Sequence Diagram.
In addition, you can also create a Subsystem by copying an existing Subsystem. Modeler copies the Subsystem's links, child items and child diagrams. For more information, see Copying items.
When used on a System Architecture Diagram, a Subsystem's notation is as follows:
When used on a Sequence Diagram, a Subsystem's notation is as follows:
In the Modeler panes, a short-cut symbol on the Subsystem's icon indicates that the item is a stub. For more information, see Stubs.
The following sections provide information about how a Subsystem is used in the model. For more information about a property, item, model part or diagram, click it.
Properties
In addition to the standard properties, a Subsystem has these properties:
Number of Instances
Visibility
Owned by
Model
Package
Owns
Comment
Constraint
Dependency - The Dependency is owned jointly by the Subsystem and the other associated item. The access permissions you have to a Dependency are determined by the access permissions of the dependent item.
Drop - The Drop is owned jointly by the Subsystem and the associated Multidrop Bus. The access permissions you have to a Drop are determined by the access permissions you have to the source item.
External Connector - The External Connector is owned jointly by the Subsystem and the associated Actor. The access permissions you have to an External Connector are determined by the access permissions you have to the source item.
General Flow Diagram
Point-to-point Connection - The Point-to-point Connection is owned jointly by the Subsystem and the associated item. The access permissions you have to a Point to Point Connection are determined by the access permissions you have to the source item.
State Machine
Defined in these parts of the model
System Architecture Model
Object Interaction Model
Shown on these diagrams
Sequence Diagram
System Architecture Diagram
Variant Diagram
Can be linked to these dictionary items
In addition to the owning Package or Model, a Subsystem can be linked to the following items.
Board - The linked Board is part of the Subsystem.
Child Subsystem - The linked Subsystem is a part of the current Subsystem.
Disk - The linked disk is part of the Subsystem.
Interface Device - The linked Interface Device is part of the Subsystem.
Multidrop Bus - The linked Multidrop Bus is part of the Subsystem.
Stereotype
Parent Subsystem - The current Subsystem is part of the linked Subsystem.
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You can make the preceding links on the System Architecture Diagram by moving the item onto a Subsystem. You can then delete the link by moving the item off the Subsystem.