Free-Space Optical (FSO) communication significantly increases the throughput of satellite networks. However, FSO links are highly susceptible to clouds and need a cloud-free line of sight (CFLOS) for successful communication. This behavior creates the need for site diversity of Optical Ground Stations (OGSs). The weather dependency leads to dynamic changes in the capacity of the link between earth and space. We develop a network model to integrate satellite networks into terrestrial optical core networks. Furthermore, we compare the inter-continental connectivity of optical core networks via submarine and satellite networks. Joint utilization of submarine and satellite networks improves the minimum availability from 95.78 % to 98.41 % for a limited capacity of at least 640 Gbits/s compared to the protected submarine network. We point out the main factors determining the availability and show the limits of the joint operation. The comparison with current satellite mega-constellations finalizes our analysis.    «

Free-Space Optical (FSO) communication significantly increases the throughput of satellite networks. However, FSO links are highly susceptible to clouds and need a cloud-free line of sight (CFLOS) for successful communication. This behavior creates the need for site diversity of Optical Ground Stations (OGSs). The weather dependency leads to dynamic changes in the capacity of the link between earth and space. We develop a network model to integrate satellite networks into terrestrial optical cor...    »