From signal flags to satellites, military comms keep advancing

Jessica Evans
Updated onApr 3, 2023
5 minute read
military communication

U.S. Navy photo by Mass Communication Specialist 2nd Class Ryre Arciaga.


It’s time to go back in time and explore the evolution of military communication technology. From signal flags to encrypted communications, the military has come a long way in terms…

It’s time to go back in time and explore the evolution of military communication technology. From signal flags to encrypted communications, the military has come a long way in terms of sending and receiving important messages. So, grab a cup of coffee, sit back, and let's dive in.

The good ol' days of signal flags

Picture this: it's the 1700s, and you're a Naval officer trying to communicate with another ship. What do you do? Well, you grab your signal flags and start waving them around like you're at a rave. Signal flags were a popular method of communication during the 18th and 19th centuries. The flags could convey messages like "we need help" or "hey, let's have a cup of tea."

But, as you can imagine, signal flags had their limitations. For starters, they were only for daytime use and the weather had to be perfect. So long battles on bad weather days? Additionally, you needed a clear line of sight between ships to use them effectively. So, if there was a storm brewing, you were out of luck.

And let's not forget the other issue: trying to decipher what those flag-waving maniacs on the other ship were trying to say. Sure, there was a codebook with various flag combinations and meanings, but who had time to flip through that thing during the heat of battle? And what if the enemy had the same codebook? It was like a game of Naval charades, but instead of guessing movie titles, you were trying to figure out if the other ship was asking for reinforcements or telling you, “The DFAC is out of meatloaf.” At least it was a step up from using carrier pigeons, right?

PASCAGOULA, Miss. - Petty Officer 3rd Class Ernesto Urbina, a boatswain's mate, organizes and stows signal flags to help prepare Coast Guard Cutter Bertholf for sea, May 14, 2008. U.S. Coast Guard photo by Petty Officer 3rd Class Michael Anderson

The telegraph and morse code

Enter the Telegraph. Fast forward to the 1800s, and things started to get a bit more sophisticated with the invention of the telegraph. The telegraph allowed messages to be sent over long distances using electrical signals. Suddenly, communication was no longer limited to a clear line of sight, and you could send messages at any time of day or night. Of course, the telegraph had its own set of challenges.

For starters, you needed trained operators who could send and receive messages in Morse code. And while Morse code may have been the "texting" of the 1800s, it still required a fair bit of skill and training to use effectively.

Plus, telegraph lines could be cut or damaged during battles, leaving you with no means of communication. It was better than the alternative: trying to shout messages across a battlefield while dodging cannon fire.

Radio communication & encryption: Hiding secrets like a boss

Ah, radio communication - finally, a way to have a proper conversation with the enemy without the need for interpretive dance. But, as with most things, it wasn't perfect. Everyone could hear what you were saying, including that nosy neighbor who always wants to know what you're up to. So, the military decided to get a little sneaky and start encrypting their messages. And thus, the birth of military encryption.

One of the earliest encryption methods was the ADFGVX cipher, which was used by the German army during World War I. Essentially, it was like playing Scrabble with your secret messages. Instead of using plain old letters, they added some spice by using a combination of letters and numbers to encrypt their messages. Now, the enemy had to decipher the code before they could even begin to figure out what was being said. It was like a puzzle that only the smartest and savviest could solve - or so they thought.

But of course, the ADFGVX cipher wasn't foolproof. The French were able to crack the code in 1918, leading to a major victory for the Allies. Point for the good guys, obvi.

Sgt. Amanda Larsen, with Company E, 106th Support Battalion, 155th Armored Brigade Combat Team, encrypts the radio in a Humvee to ensure secure communications within the unit during the eXportable Combat Training Capabilities exercise. (U.S. Army National Guard photo by 2nd Lt. Michael Needham)

Comms keep developing

Since then, military encryption has come a long way. We've gone from playing Scrabble with letters and numbers to using some pretty fancy algorithms to keep our secrets safe. But the principles remain the same - hide your message in plain sight and make the enemy work for it.

Nowadays, we've got all sorts of ways to encrypt our messages - from the classic Caesar cipher to the more sophisticated RSA algorithm. And if you want to really feel like a secret agent, you can even download an encryption app on your phone. It's like having your very own James Bond gadget, except it's not actually a gadget and you're probably not James Bond.

So the next time you're talking to your buddy over the radio, and you want to make sure the enemy doesn't know what you're saying, just remember - it's all about the encryption, baby.

The modern era of military communication

Let's take a tour through the modern era of military communication, where clunky radios and Morse code are ancient relics of the past. Now, we've got some seriously sleek and high-tech devices that even James Bond would drool over.

First up, we've got satellite communication. That's right, troops can now chat with each other from anywhere in the world. No need to rely on carrier pigeons or smoke signals anymore. This is especially important for those of you who are out there in remote areas, where the only company you've got is a bunch of camels and tumbleweeds.

Then there are drones. These bad boys aren't just for taking cool Instagram pics anymore. They're used for reconnaissance and surveillance, which basically means you can spy on your enemies without having to wear a fake mustache and a trench coat. Plus, they can relay information back to you on the ground, making them the ultimate wingman.


Now, let's talk encryption. This is the stuff that keeps your communications top secret, so the enemy can't steal your battle plans or find out where you hid the snacks. The military has developed some seriously high-tech encryption technologies, like the Advanced Encryption Standard (AES). Basically, it's like the military's own secret language, and only those with clearance can understand it. Sorry, civilians, you'll just have to stick to Pig Latin.

And let's not forget GPS. It's like having your own personal Siri who knows exactly where you are at all times. This is a game-changer for navigation and coordination, and it's especially helpful when you're trying to find the nearest Starbucks in a foreign land.

But wait, let's not forget our historical roots. Without those good ol' signal flags and Morse code, we wouldn't have the advanced communication technologies we have today. And let's give a shout-out to the ADFGVX cipher, which sounds like a code name for a new energy drink, but is actually one of the most famous military encryption technologies ever developed.

So there you have it, folks. Military communication technology has come a long way, and we're living in the age of Bond-worthy gadgets and top-secret encryption. But let's not forget our history, because those signal flags and Morse code paved the way for the technology we have today.