For Integration testing, test cases are developed with the express purpose of exercising the interfaces between the components
In system testing the complete system is configured in a controlled environment and test cases are created to simulate the real time scenarios that occurs in a simulated real life test environment.
The purpose of integration testing is to ensure distinct components of the application still work to accordance of the user requirements. The purpose of system testing is to validate an application and completeness in performing as designed and to test all functions of the system that is required in real life.
Integration testing is the phase in software testing in
which individual software modules are combined and tested as
a group.
It occurs after unit testing and
before system testing.
Integration testing takes as its
input modules that have been unit tested, groups them in
larger aggregates, applies
tests defined in an integration
test plan to those aggregates, and delivers as its
output the integrated system
ready for system testing.
The basic difference in integration testing and system testing
is about its approach and scale. In system testing the basic code level
knowledge of various modules is not required. Also the most popular
approach of system testing is Black Box testing.
So, Just to sum up, system testing consumes all of the "integrated"
software modules that cleared integration testing and also the software
system itself.The thought behind performing integration testing is to
identify and issues between different code modules that are integrated
together.System testing aims to detect defects both within the
integrated modules and also within the system as a whole single unit.