The goal of this project is to analyze video calls over the Internet Protocol (Video over IP) using a simulated IMS environment (IMS-in-a-box). The thesis presents an overview of IMS, its purpose and how it has evolved. The thesis also attempts to give the reader a full and comprehensible understanding of what the IMS is all about, its purpose and why it came into existence. The thesis considers a number of different video call case scenarios that are most likely to be encountered when making video calls over the Internet using the Internet protocol. This analysis focuses mainly on the SIP, RTP/RTCP protocols and how these three protocols are related and synchronized in order to actually know what is happening during the course of call set up and media exchange between the various end callers involved. The report looks into aspects of bandwidth consumption by the exchanged media (RTP and RTCP), jitter and its variation over the duration of the calls and the cooperation between the control plane and the user plane in order for a smooth call set up, media exchange and release of network resources. The thesis focuses on the areas of interest mentioned above, as these protocols have been identified as being of high significance in media transfer during video calls over IP.