Video and interactive Internet access in a DVB network

Modern satellite networks based upon the digital video broadcasting (DVB)/MPEG-2 standards operating on a fixed bandwidth per transponder offer two service classes. For handling of the video/audio data stream either a constant or variable bit rate is required. In general the entire transponder bandwidth is not used for video/audio services, thus data services e.g. giving the user access to Internet/WWW can be added. For the Internet/WWW access either a data carousel or an inter-LAN data transfer based upon a TCP transparent communication or a mixture of both can be implemented. This paper presents an in depth throughput analysis of a TCP transparent data communication in a DVB satellite network using the PSTN for the return channel functionality considering two different traffic models. The obtained theoretical results for the worst case traffic model are verified by means of measurements on real DVB satellite network. The results also verifies the already known recommendations for an efficient operation of a TCP network which also includes the parameter setting