LEO satellite constellations to offload optical terrestrial networks in placement of popular content in 5G edge nodes

Telecom operators are constantly searching for solutions to deal with notable growths on the data demand. One of these options consists in predicting the popularity of content to-be-requested by the subscribers on a daily basis, and store them in advance on the 5G edge nodes during the off-peak hours. To perform this placement, point-to-point optical terrestrial links are conventionally used, transmitting the same content in parallel from the operators' servers to the 5G edge nodes. One simple way to reduce this placing time consists in offloading the terrestrial (optical) network, by multi-casting over satellite (radio) the most popular content. This way, top-ranked files are transmitted only once by the satellite node, and can be received by all 5G edge nodes in coverage range. To implement the satellite segment of such hybrid backhaul solution, two options are considered: A small-sized constellation of low-cost LEO satellites with sporadic contacts with ground points, and a single high-cost GEO satellite that enables continuous pan-European connectivity regardless the location. Simulation results show that the placing time can be notably reduced using the proposed hybrid terrestrial-satellite backhauling. More precisely, the use of few LEO satellites can provide a placing time reduction that is similar to the one with GEO, even though the implementation and operational costs can be much lower with LEOs than with a GEO.