Creating External Services Based on a Master iView 
Use
You create each External Service based on a master iView. The master iView that you have to use here is chosen automatically for certain types of External Services (SAP transactions, SAP MiniApps, SAP IACs, Web addresses, BEx Web applications). In these cases you need not know which master iView is being used.
In other cases you should proceed as described below.
Procedure
To create an External Service based on a master iView:
The external service is generated based on the master iView.You now see the newly created External Service and can see which properties it has. If necessary, you can overwrite certain properties of the master iView. Also read
Maintenance of Master iView and External Service Properties.
Result
You created an external service and maintained its properties. You can insert this external service in a role. Read also
Changing External Services in the Role.