Ever Wondered How Inflight WiFi Works? Here’s the Answer.

Having to switch your devices off on airplanes is frustrating, especially when you’re on a business trip and need to stay in touch with the office or flying solo with kids on a long-haul journey. The good news is that wireless internet access is becoming available on more and more airlines in place of traditional inflight entertainment. But how in the world does it work 35,000 feet up in the air? Let’s get science-y:

First, there are two operating systems for airplane WiFi: ground-based and satellite. Air-to-ground WiFi works in a similar way to your cell phone. Airplanes have an antennae located underneath their body, which links up with cell towers. As the aircraft travels, it simply connects to the nearest transmitter on a rolling basis. The airplane becomes a hotspot, so passengers can do everything they would normally do when connected to the internet, including sending emails, making calls, and even streaming movies. However, this system can’t work when the plane is flying over large expanses of water, like on transatlantic routes. That’s where satellite comes in.

Satellite WiFi uses a network of orbiting satellites to allow connection. The satellite is linked to ground stations, and the airplane connects using a satellite antennae on the top of the fuselage. Again, the plane uses whichever satellite is nearest as it travels. Satellite WiFi operates on two different bandwidths: narrow band and broadband. Both allow passengers full internet access, although the narrower options are less suitable for streaming movies.

The number of airlines offering inflight WiFi is increasing rapidly, although it’s still not available on all routes. You may need to book directly with the airline, and some operators require a single-use pass or package from a provider such as Gogo. This is also a useful option if you fly frequently with different airlines. The price is usually higher for greater bandwidth, but for your company, it may be worth the investment.

Fortunately, inflight WiFi connectivity is poised to improve across the board. New technology such as Gogo’s 2Ku system (due to roll out this year), is steadily improving reliability, which is enabling more airlines to introduce WiFi for both domestic and international flights. JetBlue has made wireless internet service standard on all domestic flights, and Air Alaska has begun offering free access to popular social media apps like Facebook Messenger, iMessage, and WhatsApp.

Of course, easy internet access is awesome—until the guy next to you drones on for two straight hours about mortgage futures. So as inflight WiFi becomes as commonplace as beverage service, cell phone manners and other flight etiquette rules should still apply. Don’t miss the things you should never do on an airplane.