In my thesis, I introduce a performance test tool developed by Ericsson Hungary Ltd (called TitanSim) for generating network load in the IMS system. Moreover, I demonstrate this tool’s current test enviroment to make further developments. I study the theory of testing, and analyze the current tests to find the deficients of the system. I also make performance measurments to find the application bottlenecks and get informations about the IMS lab limits. During the measurements I create a step-by-step instruction that explain my decisions. When I reach the labor limits I make conclusions to detect the source of the error. I implement an independent funcion test tool in TTCN3 which is monitoring the TitanSim interface to check the order of the SIP message sequences. Furthermore I automated an Acceptance Test in an own IMS network with a bash script and with Jenkins. During my work I have learned how to use a free version control system called Git. In the end, I summarize the results I have achived and I propose possibilities for further developments.