The purpose of this research study was to evaluate the performance of real time video over IP network especially the critical real-time video for medical online applications. This study was based on experiments which involved MPEG's video CODECS. These experiments were divided into two parts and each part of the experiment was aimed to cover various metrics under study. The practical part focused on testing the performance of different video compression codecs (MPEG1, MPEG2, MPEG4) that were implemented on different IP networks (native IPv6, native IPv4, 6to4 and 6in4), to see the IP network's impaction on the video performance and the behavior of the video codecs itself under different IP networks.