Dependencies
A dependency is a kind of relationship between multiple client (source) and supplier (target) elements. This implies that a change to a supplier element may result in a change to a client element. Dependencies can be useful for representing relationships between elements in an abstract way. For instance, it can be used to represent an upper layer of an architecture stack is dependent on a lower layer of the stack.
Creating a Dependency
To create a Dependency between two items:
1. On the System Structure Diagram ribbon toolbar, click the Dependency 
button.
button.2. On the diagram, click the base item and then click the item with which you want to create the Dependency relationship. This creates a Dependency relationship between the two items.
