Application structure diagram
*An application structure diagram graphically shows first level components of an application, the access points (service point and request point) and the connections between components.
The “Purchase Request Management” application uses two IT Services: “Display purchase request list” and “Assign and handle purchase request”. The IT Service “Assign and handle DA” uses the Excel microservice.
Creating an Application Structure Diagram 
To create an Application Structure Diagram, for example:
1. Select the Application that interests you and click Create Diagram.
2. In the Create a diagram window, select Structured diagram > Internal Architecture.
The internal architecture diagram appears. The frame of the Application described appears in the diagram.
The components of an Application Structure Diagram 
An Application Structure Diagram includes:
IT services which represent the IT services used and deployed with the application.
In the example, it relates to “Display purchase request list” and “Assign and handle purchase request” services.
*An IT service is a software component of an application, that can't be deployed alone and that realizes a sub-set of the functionalities of this application either for end users of this application or inside the application (or another application). This includes batch programs.
Microservices which represent the services used independent from the application.
In the example, it relates to the Excel application.
*A microservice is a software component that can be deployed autonomously, but which does not directly provide an end user service. It can interact with other application services, applications or application systems. This is a deployable software component that uses software technologies. For example: an authentication service, a PDF file printing service.
request and service points
Service interactions between components.
*A Service Interaction represents an interaction for service purpose between entities in a specific context inside or outside a company. These entities can be enterprise org-units, applications, activities or processes, as well as external org-units. The content of this interaction is described in a service interface.
physical data stores used by the application.
*For more details, see Managing Data.
Adding an IT Service to an application structure diagram 
To describe that an application uses an IT Service, go to:
1. In the object toolbar of the application structure diagram, select IT Service and click in the frame of the application described.
An addition dialog box asks you to select the existing IT Service Name.
2. Select an existing IT service.
3. Click OK.
The IT Service appears in the diagram.