How is Integration testing & Inter system testing different from one another?

Definition
Inter-System Testing:
Test the application to ensure interconnection between application functions correctly. It does:
- Determine Proper parameters and data are correctly passed between the applications
- Documentation for involved system is correct and accurate.
- Ensure Proper timing and coordination of functions exists between the application system.

Integration Testing:
Integration testing is a logical extension of unit testing. In its simplest form, two units that have already been tested are combined into a component and the interface between them is tested. A component, in this sense, refers to an integrated aggregate of more than one unit. In a realistic scenario, many units are combined into components, which are in turn aggregated into even larger parts of the program.


How to Use
Inter-System Testing:
- Operations of multiple systems are tested.
- Multiple systems are run from one another to check that they are acceptable and processed properly.

Integration Testing:
- Interface between multiple modules are tested.
- Test combinations of pieces and eventually expand the process to test your modules with those of other groups. Eventually all the modules making up a process are tested together.
- If the program is composed of more than one process, they should be tested in pairs rather than all at once.

Hi Ajit,

Integration Testing can be of Component Integration as well as System Integration.

When we test the data flow as the navigational logic between different components / modules of a system, we could call that as Integarion Testing.

Testing the System as a whole including the backend along with the other components involved like Webserver, AppServer would be categorized as System Testing or End to End Testing.

Under the above scenario, when testing involves operations between 2 different systems which are independent in functionality as well, we would call that as Inter-System testing.

Example

Testing a Stock Exchange Application - Web based which when needed sends out Order Updates to a UNIX based application and receives feedback and further processes information.
Testing between these systems would be called as Inter - System Testing.

Cheers...

__________________
Regards,

V.Umesh Krishnan
QA Consultant

Hi Ajit

Integration Testing is done in either of the three ways 1. Top down approach or 2. Bottom up approach or 3. Bin bang approach, in which the units are tested in isolation and then integrated whole as a system and tested for its functionality. Unit in this case may be different modules existing in the application. So each modules are tested in isolation from other and then integrated as a whole application and tested.

Inter system testing is done when a system is interacting with other for data manipulation or data transfer or for flow of data. For example, you are about to create a Policy in an Insurance application, and in order to create a policy you need to know the different clients existing for that Insurance company. To know the client list, the application interacts with another Application called as Client Management System (CMS) to fetch the client list. In this case the Inter System testing is performed. This testing is done for the interaction between two systems.