What is Graph Based Models

Software testing has gained immense importance in the present competitive world of developing software more quickly, more efficiently and more accurately. Testing activity is carried out throughout the lifecycle of software development and not only towards the end of development. Time and effort required to correct errors, detected later is much more compared to those, which are detected earlier. This has direct impact on costs and has led to a splurge of research activities in this domain. Model-based testing has recently gained attention with the popularization of modeling itself. It refers to testing and test case generation based on a model that describes the behavior of the system. The OMG initiative MDA has revolutionized the way models would be used for software development. There are a number of modeling techniques in use today- some have formal syntax like Z, VDM while some are semi-formal like UML. We have made a comprehensive summary of a considerable number of research works on Model Based testing. First, the issues, challenges and problems of model based testing have been discussed. Then the different methods developed for testing or test case generation based on the models are summarized. Finally a list of model based testing tools used for testing has been collectively presented.