You can decompose one or more nodes in the framework diagram to analyze them in more detail. The decomposed node has its own sub-diagram, which models the links between its sub-nodes. Sub-nodes can, themselves, be decomposed into further sub-nodes, and so on until you obtain a sufficient level of detail.
You can decompose a node in a framework diagram in any of the following ways:
Decomposed node symbols in a framework diagram carry a plus-sign symbol to indicate that they contain further detail
The sub-diagram of the decomposed node is empty at first. You have to create the appropriate number of nodes and links between them to show their connections (see Creating a Framework Diagram).