If the results of the latest studies for Internet usage are to be believed, worldwide 12 million TV consumers will be using Internet protocol TV (IPTV) instead of the traditional TV broadcasting by the year 2010. These figures were published by ABI Research in 2006. Furthermore, analysts of Informa Telecoms & Media are forecasting the worldwide grow in revenue of IPTV to be ten billion dollar by 2010. The revolution that is described by these figures implies on the one hand an enormous increase in sales values but on the other hand causes problems in handling the data volume. Moreover, IPTV will be attracting criminal attacks like Pay-TV has in traditional broadcasting. Therefore, not only efficient encoding of media data has to be applied to save transmission capacity but also security mechanisms should be established to prevent unauthorised access. This paper will give a short overview of possible infrastructure setup as well as a method for the use of time-limited keys.