Mars to Earth communications through orbiters: Delay‐Tolerant/Disruption‐Tolerant Networking performance analysis

Abstract

SUMMARY Delay‐Tolerant/Disruption‐Tolerant Networking (DTN) architecture will be used in future deep space missions, to enable autonomous networking operations and disruption‐tolerant data communications. Therefore, it is worth analyzing the performance of the DTN Bundle Protocol (BP) in a realistic deep space environment, reproducing the characteristics of Mars missions. After a comprehensive introduction on data communications between Mars and Earth, the paper presents the essential features of both the BP DTN architecture and the Licklider Transmission Protocol (LTP), adopted here as BP convergence layer on deep space links, thanks to its ability to cope with the very long delays typical of this environment. The focus of our experiments is on analysis of the bundle flow from a Mars lander to an Earth control center through an intermediate relay node, for which two configurations are considered, inspired to Odyssey and Mars Reconnaissance Orbiter missions, respectively. Results are obtained by means of a test bed consisting of some GNU/Linux personal computers running either Interplanetary Overlay Network (ION) or DTN2 BP implementations. The analysis of results aims to highlight the role played by BP and LTP in tackling the challenges of Mars to Earth communications. Copyright © 2013 John Wiley & Sons, Ltd.

DTN performance analysis of multi‐asset Mars‐Earth communications

“…The current scenario largely extends that already considered in Caini et al 22 where data download from Mars to Earth was possible via only one orbiter, and thus, there was only one route, by contrast to the present one, which is very challenging for CGR. Moreover, this paper takes different applications as reference, with different generation rates, bundle dimensions, and priorities, all of which must be multiplexed together and then properly handled by BP and LTP, hence making the overall scenario more realistic and simultaneously more challenging.…”

“…However, since this study was conducted, BP and LTP implementations have been enhanced, and CGR has evolved significantly. Other experiments, carried out by some of the present authors, consider the case of Mars‐Earth communications 22 but are mainly focused on the impact of long delays and intermittent connectivity and do not require complex routing strategies. Finally, it is worth recalling the experiments carried out by the International Space Station (ISS), to prove the effectiveness of the DTN architecture in real space operations 23 by means of flight‐qualified DTN software.…”

Approximation of solution for generalized Basset equation with finite delay using Rothe's approach

“…Furthermore, many real-world processes and phenomena are defined by the influence of the state variable's past values, which gives rise to delays in differential equations. Caini et al [15] studied the effect of delay in Mars to Earth communications through orbiters. Kyrychko et al [27] studied the models for high-speed milling: which is a very common cutting process in the industry, a moving conveyor belt loaded with two oscillating connected masses and digital control contains handles by finite delay differential equation.…”

Mars to Earth Data Downloading: A Directory Synchronization Approach

“…To this end, we have considered a simplified variant of the Earth-to-Mars scenario already studied in the context of the "Delay tolerant network for flexible Communication with Earth Observation satellites" project funded by ESA/ESOC [13], whose results were preliminary presented in [14] and then fully analyzed in [15]. This scenario is much more complex than the basic Martian scenario studied in [16], and was built by merging inputs form ESA/ESOC with the experience of other partners of the project, including GMV, DLR, Solenix and University of Bologna. Even in the simplified version considered here, this scenario is quite representative of future interplanetary environments, which is essential to draw general conclusions about the real applicability of the proposed approach in space.…”