System Integration Testing is a process in which the testers verify that all the systems which are related and dependent on each other maintain their data integrity. System Integration Testing involves overall integration of all subsystems of a complete system.
This integration testing uses the black box testing technique to test the system. The objective of the System Integration Testing is to check and verify whether all the software components are executed properly. It also verifies that all the software modules which are dependent on each other are functionally correct and their data integrity between the subcomponents which makes the entire system is also checked. System Integration Testing also known as Integration testing is one of the phase of software testing in which all the individual modules are combined and tested as one group.
Consider an example of System Integration Testing:
Consider a Bank named ABC Bank. Let us assume that a customer wants the loan and he comes to the bank for his home loan. Customer gives all the documents required for the loan and the bank gives him the loan after accepting and checking the documents and details like his balance, properties, etc.
System Integration Testing (SIT): This SIT will check the system (bank system) as a whole and depending on the functionality it will check whether the front end(address, contact details, etc.) data given by the customer again reflects i.e. it again shows the same details in the front end wherever required/possible. SIT will also check third party application such as in this application to generate the interest information, payment information, etc. if we are using some other application which is not related to this application but integrated to this to fulfill some task so testing all this functionally as a whole.
Thus the system Integration Testing checks whether all the dependable modules are working properly. System Integration Testing involves various techniques as given below:
- Top down Integration testing technique
- Bottom up Integration testing technique
- Big-Bang Integration testing techniques