A software testing system includes a test interface and a verification interface. The test interface receives a first processing request for the application program under test. The test interface generates a second processing request equivalent to the first processing request, and communicates the first and second processing requests to the application program under test and a model of the application program, respectively. A verification interface compares a first and a second response data set received, respectively, from the application program under test and the model. The verification interface generates an error indication if a difference is determined from the comparison of the first and second response data sets. If a difference is not determined from the comparison, then the verification interface generates a success indication. The verification interface communicates either the success or error indication to the test interface.