Architecture and analysis of a satellite downstream boost for xDSL networks

The need to provide broadband in a uniform manner to all European citizens, regardless where their home is or what is their country, is pushing for a long time the scientific community to find alternatives to terrestrial xDSL, colliding with the need to have solutions that are not too expensive in terms of infrastructure and deployment costs. The project SAT4NET, funded under the ARTES 1 program of the European Space Agency (ESA), has the goal of analyzing the technical and economic feasibility of an integrated xDSL/satellite network architecture. The key idea is to exploit the very broad coverage of satellite to provide additional bandwidth to users in a digital divide situation, only when they need it, so as to keep the commercial offer to the users competitive with respect to similar offers by pure terrestrial telecom operators in densely populated areas. In this paper the architecture of such a hybrid network is outlined, along with discussing the key design choices that were identified in the study. Furthermore, results from the performance evaluation study of the network, based on packet-level simulations, are reported to show the effectiveness of the main proposed solutions.