DTN for LEO satellite communications

Satellite communications are an interesting and promising application field for Delay/Disruption Tolerant Networking (DTN). Although primarily conceived for deep space communications and sensor networks, it was immediately recognized that DTN was applicable to satellite environments, in particular to cope with the intermittent channels typical of LEO (Low Earth Orbit) constellation satellite systems. The aim of this paper is to assess the advantages of DTN when applied to LEO satellites. Qualitative assessments are supported in selected cases by preliminary results obtained on a testbed based on GNU/Linux machines. In particular, two application scenarios have been considered, both using a single LEO satellite. In the former, we have one LEO satellite for Earth observation, connected to its gateway stations only at intermittent scheduled intervals due to its orbital motion. The latter is one LEO satellite acting as a “data mule” between a terrestrial sensor network and a remote satellite gateway station, which are never in the satellite coverage area at the same time. The results show the feasibility and the advantages of DTN in LEO satellite communications.