SpaceX's plan to put a whopping 4,425 satellites into low earth orbit (LEO) is the boldest plan for adding global non-terrestrial broadband capacity, but it isn't the only one by far.  Eleven companies filed plans describing non-traditional – non-geosynchronous (GEO), lower flying, many satellites – network with the Federal Communications Commission (FCC) at the agency's November 15, 2016 deadline. 

Companies asking for licenses for new cloud-style satellite broadband networks include established aerospace firms including Boeing, O3b, Telesat, ViaSat and upstarts Audacy, Karousel, Kepler, and Theia, according to tweets from Space News Paris bureau chief Peter B. de Selding.

But SpaceX clearly has the most audacious plans, and not just in the total number of satellites.  SpaceX plans to build and launch the constellation itself, as well as build its own ground-based gateway equipment and user terminals - essentially owning and controlling the entire ecosystem.  Nearly all other satellite operators hire one company to build a satellite, another to launch it, and sub-contract with other firms to build gateways and user terminals.  It remains to be seen if SpaceX can keep everything in house or will ultimately farm out some pieces, but the company took a similar approach with building the Falcon 9 rocket, keeping nearly all the vital production in-house rather than relying on external vendors. 

The initial SpaceX constellation will be made up of 1,600 satellites, deployed in 32 orbital planes, with 50 satellites per plane, according to documents it filed with the FCC.  Final deployment will be made up of 2,825 satellites in additional orbital planes, providing full and continuous global coverage of 1 Gbps speeds.

Each satellite will weigh in at about 850 pounds, orbiting between 714 to 823 miles above the Earth -- higher than the International Space Station's 286 or so mile orbit, but far lower than the 22,000ish orbit of an old-school geosynchronous telecommunications satellite.  The satellites would use Ku and Ka-band radio frequencies between ground and satellite and laser communications between satellites in orbit, hopping between satellites as necessary to relay signals around the world.

Musk and other proponents of cloudsat networks say the broadband service can be as good as or better than fiber optic broadband when it comes to latency issues.  Since signals don't have to travel through glass and wind along cable paths, there's less delay introduced in the communications path, but no one has yet built and operated a large scale cloud on such a scale, nor has anyone in the public eye deployed satellite laser communication cross-links in commercial production.

SpaceX may have size, but to be sure, there are many others wanting to play.  Boeing has asked for permission to launch a 60 satellite Ka-band constellation in three different planes, with satellites flying between 17,000 to 27,500 miles above the earth -- clearly, Boeing is less about latency in its project and more about coverage and redundancy.

O3b currently operates a constellation of 12 Ka-band satellites orbiting at around 5,000 miles above the earth, significantly cutting down latency from existing communication satellites. The company wants to add both new radio frequencies and more satellites to its network with another 40 satellites to continuous 24 x 7 coverage.  Currently, a customer gets 360 minutes of service four times per day, but speeds go up to 1.6 Gbps at latencies of under 150ms, far faster than a 500ms geosync data connection.

Two projects come from Canada-based companies. Telesat, one of the largest commercial satellite operators, has filed to put up 117 Ka-band satellites in a pair of orbits at 621 miles and 775 miles.  The high-speed network would provide continuous coverage across all of Canada and the North Pole, providing a key resource for the U.S. and the Canadian militaries.

Start-up Kepler wants to launch up to 140 3U-sized Ku-band Cubesat satellites at 310 to 400 miles above the earth for a global Internet of Things (IoT) data network, reports SpaceRef Canada. Kepler's satellite will use software defined radio and electronically steerable antenna arrays to relay data faster and cheaper than the existing crop of IoT satellite services from Globalstar, Iridium, and Inmarat.

And current broadband service provider ViaSat filed a proposal to put up a constellation of 24 Ka-/V-band satellites operating around 5100 miles above the earth. ViaSat has been loudly preaching the virtues of its geosynchronous Ka-band ViaSat satellites in orbit and in the pipeline.  The company boasts that its ViaSat-3 family of geosynchonous satellites will have terabit-per-second throughput when launched in a couple of years.

All of these proposed cloudsat networks are subject to getting funding and investor support. Filing the paperwork doesn't guarantee the construction of a new network. Start-ups such as Kepler may have an easier time raising tens of millions for building and launching breadbox-sized Cubesats than Boeing and Telesat might with the billions required for larger satellites.