Appearance
Defining Interfaces 
The arrow(s) between two architecture elements are the interface between those elements.

Creating an Interface Definition 
If the arrow or interface between two architecture elements is selected in the Development tab, the interface definition view is shown in the bottom right. A new interface definition can be created by clikcing on the 
 button.

Each singular interface can be described as matter, information, or energy. Additionally, it is possible to describe the interface logically (ideal for an early phase of the product development) or physically (necessary in a later phase). It is also possible to customize pre-defined interfaces if needed.