The use of COTS (commercial-off-the-shelf) components for system development has been a growing trend in the software engineering community during the past decade. However, the engineering of COTS-based systems involves significant technical risks. A good indicator of the as yet unresolved difficulties in COTS-based system developments is the relatively poor understanding frequently regarding the processes associated with development of the "glue code" used to integrate COTS components into the system, as well as with the other integration activities. The main objective of the paper is to understand how the glue code development process and the COTS component integration process affect each other and how they affect development effort and schedule throughout the development life cycle, based on given parameters via software simulation that provides a method for checking the understanding of the real world process and thus help people produce better results in the future.