Energy-aware Routing Algorithm for DTN-Nanosatellite Networks

Satellite constellations are envisioned as meaningful transport networks to forward data throughout the world. Low Earth Orbit (LEO) satellites are the most appealing for this purpose due to their low altitude which allows guaranteeing certain performance, especially in terms of delivery time. Mega-constellation of small LEO satellites (micro- and nano-satellites) are planned to be employed to cover the entire Earth's surface. However, these satellites have several constraints which affect the data forwarding process and have to be taken into account. Energy is one of these constrained resources. Energy storage and recharge are limited by the reduced battery capacity and solar panel surface area, while telecommunication hardware energy consumption is considerable especially in case of high traffic volumes. In this paper, we propose a novel energy-aware routing algorithm based on the Contact Graph Routing (CGR) called E-CGR. E-CGR exploits static and known a priori information about contacts (begin times, end times, and overall contact volumes) to compute complete routing paths from source to destination which are then validated and confirmed from the energy viewpoint.