Developments towards an Interplanetary Internet

A major effort in current developments for future space missions is the improvement of communications capabilities. With increasing interest in space research and long-term exploration programs including a variety of both near Earth and deep space missions of the major space agencies, communications faces additional challenges. Next-generation communication systems must be able to cope with long-distance communication links, supporting disruption-tolerant networking (DTN), implementing efficient store-and-forward strategies for data download, and providing interoperability between missions. Therefore, innovative concepts for the creation of an Interplanetary Internet (IPN) are currently under investigation. The Interplanetary Internet Special Interest Group (IPNSIG) has already elaborated a suitable IPN network architecture and identified key research areas. Since the main challenges for IPN are efficient data transport strategies, current research activities are focused on the transport layer. However, in order to achieve these goals, improvements at all OSI layers are necessary. The presented paper deals with future developments required for the establishment of an Interplanetary Internet. After introducing an IPN network architecture proposed by [1], the suitability of terrestrial Internet and existing space communications standards for IPN is analyzed. Current protocol developments for IPN are introduced and compared with the previously investigated standards. Finally, future IPN developments are presented. This analysis focuses on all OSI layers, providing a set of recommendations for the improvement of existing technologies and proposing some innovative concepts and solutions.