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Internal Block Diagram

The Internal Block diagram provides a way of viewing the composition of a block using part properties connected together using ports and connectors. The diagram is useful for showing a Block's (represented by the diagram frame) composition and the flow of inputs and outputs between the various parts that make up the block, when required the direction of flow can be indicated on the connectors.


The main elements that can appear in Block Definition diagrams are:

  • Property
  • Connector Property
  • Distributed Property
  • Flow Property
  • Bound Reference
  • End Path Multiplicity
  • Signal
  • Port

The main connectors  that can appear in Block Definition diagrams are:

  • Item Flow
  • Connector
  • Binding Connector
  • Dependency


A variety of tools can be used with structural modeling and Internal Block diagrams, including:

  • Diagram Filters - which allows a user to filter elements out of the diagram to achieve a more specific focus,
  • Pan and Zoom - which allows a modeler or viewer to easily move around large diagrams,
  • Spreadsheet (CSV) Import and Export - which allows content in spreadsheets to be imported or exported from the model,
  • Documentation - which allows formal or informal documentation to be generated from the model in a variety of formats,
  • Traceability - which provides a hierarchical view of an element's relationships to other model elements,
  • Responsibilities Window - which provides a composite view of the important responsibilities of an element, including Constraints, Requirements and Scenarios
  • Relationship Matrix - which allows the connections between Blocks (or other elements) and other elements such as Requirements and Use Cases to be visualized in a matrix.


The Internal Block diagram is used to model the internal structure of a block including its parts and the relationship between those parts.