A test system (and corresponding method and computer program product) for generating unit tests for a heterogeneous network system and validating test results to ensure that the network system functions properly is described. In one embodiment, the test system is an appliance that is capable of normalizing communication protocols supported by component systems of the network system. The test system creates objects and methods corresponding to component systems and their supported protocol commands in the network system, and generates unit test cases based on the objects, the methods, and the normalized protocols. The test system transmits the unit test cases to the component systems, receives test results, and validates the test results to ensure that the network system functions properly.