Integration Scenario Model 
General
An integration scenario model (SAP integration scenario model) shows all the deployment units and process components involved in an end-to-end scenario. It gives a complete overview of the end-to-end scenario to better understand the whole process and to see which interactions are necessary between the process components involved.
Recommendation
Some process components are of such importance that you need to connect them to almost every other process component. This, however, gives an incorrect impression of the actual process flow. Work with placeholders in the integration scenario model to avoid this. Only connect the placeholder with a process component if the interaction is essential for the understanding of the end-to-end business scenario. In the graphic below there is an example of a placeholder for the Accounting process component.
The following graphic shows the structure of the model:
Typical Structure of an Integration Scenario Model
The model does not present any details as in a data flow diagram. By using the arrangement of the process components in the model you can, however, model the typical process flow of the scenario.
Process Component Types
The following process component types are available:
Process Component
Process component that you implement in your own business.
Process Component at Business Partner
Process components at business partner that is connected by B2B communication with a process component in your own business and in this way enhances an intra-enterprise value chain.
Third Party Process Component
Third party process component that is connected by A2A communication with a process component in your own business. In contrast to the process component at business partner, the third party process component is integrated in the business software.
Interaction Types
The interaction between two process components shows how two process components exchange data with each other or what technology this data exchange is based upon. You can use the interaction types:
Enterprise Service Interaction, shown as dark blue.
Implemented outbound from service interfaces in the Enterprise Services Repository.
Web Service Interaction, shown as yellow.
Represents synchronous point-to-point communication.
Direct Interaction, shown as green.
Interaction must be implemented in a deployment unit. For this type of interaction it can be a matter of, for example, access to a common database or a local RFC call.
Other Interaction, shown as light blue.
Further interactions between process components of different deployment units which are not enterprise service or web service interactions.