People began dreaming about LEO internet systems because they wanted to expand on the capabilities offered by existing satellite options. Today’s satellite internet systems transmit signals from fixed locations 22,000 miles over the earth to a ground station, then to a small antenna at the subscriber’s location. It’s a long trip, and subscribers pay for it in various ways.
The benefits of satellite internet are obvious in places where land-based network infrastructure doesn’t exist. But while systems based on high-orbit satellites need only minimal ground equipment to reach remote places, a range of complications – including cost, speed and performance – prevent them from being a global solution. LEO systems aim to get past the problems by getting closer to earth.
The rationale for developing LEO satellite internet solutions is based on a simple calculation: Satellites operating closer to users support better performance. Of course, being closer (anywhere from 100 to 1,200 miles away) means that the satellite signals can’t cover as broad an area. But LEO satellite internet providers plan to compensate with more satellites, and say they’ll launch hundreds and even thousands of them in “constellations” that can provide the coverage they need to reach subscribers.
Even if constellations of internet satellite successfully go into orbit, the systems will need highly interconnected networks on the earth. That’s because LEO satellites are non-geostationary, meaning they aren’t in a fixed location over the earth, but continuously pass overhead. Coverage is achieved through constant “handing off” between satellite and ground stations, and that requires a lot of ground-based interconnection points. Plus, the systems all still depend on traditional terrestrial networks.
Say, for example, a person sends data that’s destined for Chicago from a remote area in Australia. That satellite is moving when the data hits it, and it needs to bounce through a string of other satellites that are also moving to get to Chicago. This happens using SDN technology, and it’s not always a matter of moving between the points in the straightest line possible.
Because these new systems use free-space optics (which rely on lasers rather than radio frequency), clouds can impact transmissions, so weather conditions must be accounted for. That takes a flexible network of ground stations, to enable the system to select a ground station free from weather worries, then pick up a terrestrial network and complete the transmission. A global interconnection platform becomes an essential part of this system.
That platform can house and interconnect those ground stations, as well as the range of terrestrial networks that will come into play all over the world. Having everything on the same interconnection platform, linked by the same interconnection fabric, supports the essential secure, many-to-many, real-time connectivity that LEO internet systems will depend on.