Moon to Earth DTN Communications Through Lunar Relay Satellites

Although Delay-/Disruption- Tolerant Networking, which originated from research on an Interplanetary Internet, has enlarged its scope to encompass all challenged networks, space applications are still one of its most important application fields. This paper deals with DTN communication from Moon to Earth, based on the use of a lunar satellite acting as a “data-mule” to collect data from a Lander located on the far side of the Moon. To make the scenario more interesting and complex from the point of view of possible security threats, we assume that data must be transferred to a non-institutional user connected to the Space Agency Control Centre via Internet. In particular, the paper investigates the state-of-the-art ability of ION, the NASA implementation of the DTN Bundle Protocol (BP), to cope with the many challenges of the space scenario under investigation, such as intermittent links, low bandwidth, relatively high delays, network partitioning, DTN routing, interoperability between LTP and TCP BP Convergence layers and security threats. To this end, the first part of the paper contains three brief overviews of the DTN architecture, the Bundle Security Protocol and the ION implementation. These facilitate comprehension of the following sections, dedicated to a detailed description of the experiment scenario and, most essentially, to the in depth discussion of the numerical results obtained with the latest ION version (3.0).