Terrestrial or satellite? for internet broadband network

摘要

Expansion of the Internet to Broadband services such as VOD, Broadcasting, Teleconferences, Distance education, etc. is expected to grow rapidly. However, solution of many difficult technical problems are required for its realization. The processing overload on the tranmitting servers and QOS degradation due to network congestion will make the service impossible without realization of a universal Multicast through the Internet. However, it is unlikely that such multicast becomes available soon as shown by a simple analysis conducted in this paper. On the other hand, the satellite communication is readily available to provide a universal multicast function as proven by the established market of the Direct Satellite Broadcasting(DSB). It is natural to combine the satellite networks with the Internet to mix the features of both networks. Some such Satellite Internets have been in service for a few years. In this paper, some Broadband Internets, Satellite communications and Satellite Internets are compared in terms of broadband and cost performances. Finally a brief view of the new satellites with many beams and onboard switching functions is given with expectations for the new satelite internet development.