IP-based networks for multimedia services - such as IPTV - are increasingly spreading in the world. Providing the interactive features and user experience related to the IPTV services had to have a necessary condition met: the spread of broadband access networks. The ever-changing business needs and the technical development of the system are keeping the IPTV-service constantly evolving. In addition, the IPTV service requires high availability. These facts create different challenges to the IPTV platform operation engineers. In this thesis we touch upon the largest Hungarian telecommunications service provider's operating methods, which are essential for high-availability service. After obtaining informations from the IPTV Platform's architecture and the measurable indicators of the availability, this thesis discusses the process of troubleshooting errors. There are also other corporate groups essential in the success of the IPTV service, such as the one responsible for the access network. At the end of the thesis we examine the cooperation with these group.