If instances of Blocks “communicate” with each other use an Association between them.

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Note kind
TIP
Policy level
SUGGESTED
UML keywords
Association
SysMLv1.x keywords
Block
Keywords
Relates to
Dependency vs Usage vs Association vs Connector
Association vs Connector - detailed
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Related snippets (extracts)
  [UML-2.5.1] A Connector specifies links that enables communication between two or more instances.
  [UML-2.5.1] In contrast to Associations, which specify links between any instance of the associated Classifiers, Connectors specify links between instances playing the connected parts only.
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