The Structure diagrams available in SysML are:
•Block Definition diagram
•Internal Block Definition diagram
The Block Definition and Internal Block definition diagrams are modified UML 2.0 diagrams while the Parametric diagram is new. The Package diagram follows the UML 2.0 standard.
Blocks are used to describe the structure of an element or system, and can have multiple compartments that define its characteristics. Note that behaviors can be assigned to a block.
•Block Definition Diagrams describe the relationship between blocks: associations, generalizations, dependencies.
•Internal Block Diagrams describes the internal structure of a block in terms of properties and connectors between properties, i.e. the relationship of its constituent parts; using ports, connectors, and flows.
•Parametric diagrams use constraint blocks, defined in a Block Definition Diagram, to constrain the properties of other blocks in the Parametric diagram and integrate engineering analysis with design modeling.
•Package diagrams organize model elements into packageable elements and define dependencies between the packages and/or model elements within the package.