Mark Zuckerberg is determined to bring Internet access -- and thus Facebook access -- to every corner of the globe, no matter how remote. On Friday, the social network's CEO said more about how he plans to do that, and it involves drones, satellites and even data-carrying laser beams fired across space.
Zuckerberg didn't exactly take a potshot at Google, but he did mention twice why he thinks drones are a better option than balloons for beaming Internet access to remote places. Balloons, of course, are the main communications vehicle for Google's Project Loon.
With drones, Facebook will be able to "precisely control the location of these aircraft, unlike balloons," Zuckerberg wrote in a paper on the topic. And drones, he said elsewhere, "have more endurance than balloons."
The battle for the skies has commenced.
Different parts of the world require different technologies for Internet access, based on factors like population density and the size of the area to be covered. Zuckerberg described Facebook's approach to the problem in the paper he published Friday.
Some 10 percent to 20 percent of the world's population lives outside the range of 2G and 3G wireless networks, and many of those people are in remote areas where building physical networks on the ground is "uneconomical as well as impractical," he explained.
One option Facebook is considering is "free space optical communication," or FSO, which uses light to transmit data through space. "These are basically invisible laser beams in the infrared part of the spectrum," Zuckerberg says.
FSO would allow the company to dramatically boost the speed of Internet connections provided by other platforms such as satellites. Its speed is on par with fiber-optic networks, Facebook says. But the narrow optical beams must be pointed very precisely. "The level of accuracy required is the equivalent of needing to hit a dime from 10 miles away, or hit the Statue of Liberty from California," he says.
They also require "line of sight" visibility, meaning they won't work well in bad weather. That makes FSO a bit of a long shot, but Facebook has hired "world experts" in FSO and will try to keep improving the technology, Zuckerberg said.
Drones, on the other hand, are one of the major areas where Facebook is focused. Flying at 65,000 feet and powered by solar panels, drones can broadcast a powerful communications signal that covers an area the size of a city with a medium population density.
Facebook recently said it was bringing on team members from Ascenta, a U.K.-based company that created early versions of the Zephyr solar-powered unmanned aircraft. Facebook is building its first drones now and expects to have an initial version working in the near future, Zuckerberg said.
Facebook's drones might be able to stay aloft for months or years, he writes -- which is longer than the 100 days or so that Google has said its balloons could stay up in the stratosphere.
In large areas with low population densities -- think deserts -- Facebook may launch satellites as a cheaper alternative to drones. They'd be deployed either in low Earth orbit up to 2,000 kilometers overhead, or in geosynchronous Earth orbit, much higher at roughly 35,000 kilometers above sea level.
In low Earth orbit, the satellite's signal could provide access to fewer than 100 people per square kilometer, Zuckerberg said, with an even weaker signal provided by satellites higher up. But the FSO system could help speed that up.
For densely populated urban areas, mesh networks can be simple to deploy and cost effective, Zuckerberg said. Facebook will say more about those plans at a later date.
Zuckerberg touted some of the success the company has already had with the project, which it calls Internet.org. In the Philippines, it worked with a local operator to provide "free data access" to its apps, to make it easier for people to register for data plans, or in some cases to get loans for a plan. "In just a few months we helped double the number of people using mobile data on Globe's network and grew their subscribers by 25 percent," he said.
Working with another operator in Paraguay, Facebook helped grow the number of people using the Internet by 50 percent, he said.
The two partnerships together helped almost "3 million new people" access the Internet, according to Zuckerberg.
Internet.org is not only about providing access to Facebook, he said. It's also intended to help people get access to jobs, financial services and health care.
The entire project could be a big investment for the company. Looking at satellites alone, even if Facebook can build them cheaply and make them work, transporting them into space could cost hundreds of millions of dollars, Zuckerberg said, and there are regulatory issues, too.
And, of course, it will have to make sure its drones don't collide with one of Google's balloons, which would open up a whole new level of competition.