( music playing ) Wait. That's the cable? I was expecting something so much bigger.

That's the internet. To get across the ocean, nearly all internet traffic has to use a cable like that one. - It's tiny.

I'm so surprised. - You're actually surprised. I know, I could tell.

Love it. All right, let's go get some hard hats. Cleo: If you're watching this YouTube video anywhere outside of the United State, this is probably how it's getting to you.

For most of us, the internet is virtual. It's made of Instagram posts and e-mails and YouTube videos. But it's also a physical thing, and what it's made of and where it goes matters for how we use the internet now and who will be benefit in the future.

So I want to know how does our internet really work and what comes next? ( music playing ) ( music playing ) The decade I was born, people were still learning about the internet, and they didn't exactly consider it crucial. But, you know, I think about this.

What about this internet thing? What the hell is that exactly? And they call it the World Wide Web.

You can e-mail anyone. What the hell is e-mail? Man: Can you believe what's possible these days?

Conversations through your computer. Cleo: But now it seems we can't even function without it. Jobs require online applications.

Parents around the country know that their kids can't get an adequate education without internet access. I mean, people tweeting that they needed to be rescued and a boat came in. It's truly been life saving.

The internet has become essential to us, but a lot of us still don't know how it works. Okay, I need you to close your eyes. - All of us?

- Just trust me. Just close your eyes. Yeah, for real.

I'm serious. Close your eyes. What's the craziest thing she could show us - when we open our eyes?

- ( laughs ) - I hope it's kittens. - Okay, now you can open them. ( screams ) - Joss: Tiny people!

- Alex: They're us. Christophe: It's tiny us. So I know that there are three major parts of the internet.

We are on this outer ring. They call it the last mile, but really it's the first and last mile. So it's the texts we send, the notifications we receive, the apps we use.

Everything we do to connect or receive information from the internet happens in this first and last mile. And we are inside. .

. the Vox office. Also out in this outer ring are houses.

- You guys wanna help me put these down? - Yes. - Trees.

- So all of the-- all of the trees and all of the houses, all Wi-Fi, which uses routers somewhere in our office or somewhere in your home, and all cell service, which means that you're paying a cell tower a little bit further away, but still pretty close by. All this wireless technology uses radio waves to send signals into and out of the internet. I'm gonna show you how this works.

But first, I'm gonna take a selfie. Perfect. Okay.

So this is our selfie. I-- ( laughs ) - Joss, you've nailed that face. - Yeah, it's my go-to.

So I'm just gonna send this to you via e-mail. - Typical e-mail. - Typical e-mail.

- There it is. - Boom. - Ta-da.

- So my goal is to figure out how my e-mail got from my phone to yours. In order for my e-mail to get from here to here, my phone takes that photo and cuts it up - into more manageable packets. - No!

- We've been decapitated. - Just-- - Christophe: Just me. - Just you.

- So, imagine each packet like a letter in an envelope. - Uh-huh. So, each envelope gets a header, which is a little bit more information that includes-- - Christophe: Where it's from.

- Where it's from and where it's going to, and a bunch of other things that we're not going to talk about. So the format of each header follows a set of rules, and you can think about these rules like the rules of the online postal system. How everything is packaged and sent and received on the internet.

So you've probably heard people say that everything that happens in our computer is ones and zeros. - Right? Binary.

- I have. Yeah. Cleo: Which we can think of as a kind of Morse code your computer understands.

And everything that you send over the internet - is also binary. - Mm-hmm. Christophe: ( gasps ) What?

- Ta-da! - When did this happen? - What?

- I do magic now. - Okay. - Incredible.

So, each one or zero is a bit and eight bits is a byte. So, if this photo was 1. 1 megabytes that's 8,800,000 ones and zeros.

So, somehow these binary ones and zeros have to get onto radio waves to be transported - to the router, right? - Exactly. Yes.

- Okay. - And that's where I got stuck. So, I called up Sundeep Rangan, who specializes in computer engineering at NYU.

How does a wave carry binary information? Ah, that is a very good question. So, the simplest thing you could do is every time you want to transmit, say, a zero, you could transmit one frequency.

And every time you want to transmit a one, you transmit a different frequency. And then as long as the receiver can detect which frequency it is, it can know it's a one or zero. That's actually called frequency modulation.

Is it also fair then to say that at its most basic, a cell phone is a radio? Sundeep: It is a radio. It is absolutely a radio.

Okay, so waves with binary information have to get from my phone to the router. But then at the router, they have to be turned into something else that can go out the back of that device along cables to get to their next location. Depending on what the wire is made of, it's either gonna be pulses of electricity if the wire is copper, or pulses of laser light.

Sundeep: So, it's a laser and it just turns on when there's a one, it turns off when it's zero. So, faster than this. - A little bit faster than that.

- Faster than this? So our photo went from binary to radio waves - to little flashes of laser light, right? - Yes.

Where does it go after that? We're about to find out, but I'm gonna take Alex. - You're not taking me?

- No. It's his turn. I gotta go.

Ooh. So, the wires out of the back of our router connect to other wires inside out office, which are owned by our internet service provider - or ISP. - Alex: Okay.

And they're responsible for looking at the header of each of those envelopes and figuring out the most efficient route to get to its next location, which is an internet hub. - Alex: And where would that be? - Cleo: Right there.

That's an internet hub. - Alex: This old building? - Cleo: Yeah.

- All right, let's go. - It looks just like every other office building I've ever seen. Greg Sisk: Well, it started as Western Union's headquarters.

So, it supported telegraph operators back in the day, and it's migrated to today where it's supporting the internet - here in lower Manhattan. - That's poetic. So all those wires all need to come to a place like this to connect between networks.

So, for our example, our ISP in the office has a network. And AT&T, which is Christophe's cell provider, has a network. And in order for my e-mail to get from my phone into Christophe's phone, all of those networks have to send those ones and zeros across those wire pathways.

There's so much that happens in that split second that you connect. So there's really no such thing as a cloud or any type of magnanimous-- - The cloud is a marketing term. - Yeah.

Cleo: The thing that I find really amazing is that, like, my e-mail is one of the millions of messages flowing through these cables. That feels really abstract, but it's actually-- there's a message to somebody's mom and there's a college application and there's a job offer. And there's a dank meme in here somewhere.

( music playing ) Okay, so my e-mail became a series of waves of light that travels over the tubes of the internet. But what if I wanted to send it somewhere really far away? Somewhere on the other side of the world?

We're in Newington, New Hampshire, to go to a factory that's gonna show us how the internet works at long distances. We're headed into the third layer, the internet backbone. Oh, that's the cable highway.

What's the cable highway? Cleo: That's where the cables go from the factory down to the dock. The company we're gonna go see, SubCom, is one of the top four submarine cable providers in the world.

There's the ship. - All right. - Hi.

- Hi. I'm Alysia. - Hi.

I'm Cleo. - So nice to meet you. - Nice to meet you.

Alysia: This is the SubCom Decisive. She is a custom-built cable installation and maintenance vessel. She's 139 meters long, which is about 450 feet.

- Wow. - Yeah. Cleo: The engineering and material science at work here are incredibly complex.

But the basic process is actually really simple. Light goes in on one side of the ocean and comes out on the other. So, as the Decisive moves across the ocean, the internet cable is gonna come out the back and be laid down behind it.

And sometimes it's gonna be buried in the ocean floor by that machine right there. But most of the time it's just gonna lay there on the bottom of the ocean. So, these are the two types of cable that we have, the two basic types.

So this one, this is called lightweight cable. So that's the one that we would use in the middle of the ocean. And then this piece is the stuff that we use the plow to install and actually bury.

And the cable is engineered to be super strong in a lot of ways, but it is also very delicate in a lot of other ways. Cleo: The wires that carry the light waves themselves are typically made of fiberglass, literally just a continuous strand of glass about the size of a human hair. Why is it that there are so few fibers?

We're working on trying to put more fibers inside the cable to get more data into each fiber to make it so that we can send more information than what we already have. ( music playing ) Whoa! - So that's the cable tank.

- Whoa. Slow, slow. We got the pipe.

We got the pipe. Alysia: Work it over. Work it over.

What we're doing is we're loading it into the tank in a continuous spool, right? Is it, like, 10 tons, 50 tons? Oh, we're loading ten tons in a day.

Cleo: Oh, my God. Cool. Alysia: It's gonna end up being about 60 days of plowing.

- Wow. - Yeah. Alysia: So, 70 days total to prep and install it.

Okay, on the highway you have two minutes until cable starts. What do you want? Cleo: What blows me away is just how much hard physical labor is required to make the internet work.

Thank you. The craziest thing is that this cable is one of about 400 exactly like it that create a web around the Earth. - Oh.

- Wow! So we're just gonna lay down the undersea cables of the internet so that we can see where they go. Christophe, you get Africa, and I'll give you part of Europe.

Joss: I love the one that goes across the Great Lakes. Cleo: You guys wanna see what the internet actually looks like? - Yeah, totally do.

- Okay. - Whoa. - Wow.

- Whoa! - That's crazy. Oh, there's, like, all this metal in here.

Seems like a shark could take a bite out of that pretty easily. - I was gonna say the same thing. - I'm so happy you said that.

- Does that happen? - Yes. So there's this video of a shark biting a cable like this of the internet.

- Oh, there he is. - He's a big boy. Big boy.

Nom. - Oh, doesn't taste good. - Oh, that probably hurt his teeth.

- I know, poor guy. - He didn't like it. So, after that video went viral in 2014, the Internet Cable Protection Committee, released this report that has my favorite title of any report of all time, which is "Sharks are not the Nemesis of the Internet.

" The vast majority of faults are caused by human activity. - It's, like, fishing, anchors. - Anchors.

- Drlling. Yeah. - Stuff like that.

Woman: The kingdom of Tonga has faced a cell phone and internet crisis after a fault in a fiber optic submarine cable cut its main connection with the world. Cleo: In January 2019, experts believe that an oil tanker dragged an anchor across the seabed here, which of course caused a really big problem for Tonga. What is the problem?

If it's in land, when it's in land, it's all in land in Fiji, a quick fix. But if it's in the water? Ooh-ya, ooh-ya, ooh-ya.

It's gonna take a long, long time. And it took 13 days to get the internet back. - 13 days.

- Long days and nights. That's a long time. So if you live in one of these heavily connected places like the United States or many, many other parts of the world, it is very, very unlikely that an anchor cutting a part of your internet is gonna interrupt your service.

But what happened in Tonga does call attention to how important this infrastructure is and how much we rely on it. I feel like, I mean, I've never lived in a time when all of these tools were not part of my daily life. It's kind of sad that it's not something that's available to everyone.

Yeah, exactly. There are lots of people that still don't have reliable internet access in the first place. I wanted to find out more about how we could actually solve that problem.

( music playing ) So we're here in Nevada to see a company that's helping more people get access to the internet. But before we get there, I have some maps to show you. This is a basic map of the internet backbone in the United States.

You can tell just by looking at this map why it might be that some people have a hard time getting low cost, high speed internet. Companies aren't as incentivized to lay fiber optic cabling where there are fewer people there to pay them for it. The same applies to low income areas.

This map shows the areas that researchers call uneconomic for companies in red, meaning that the typical monthly costs exceed the expected monthly revenue. In many of these red areas, people only have one or two options for internet service providers, meaning that those service providers can jack up the costs. The darker the country, the more people there are paying for internet service.

So there's a lot of variety around the world and even within countries in terms of who has access to the internet and at what cost, and that has a huge impact on people. ( music playing ) If you haven't heard about 5G, get ready for a faster internet connection. Man: 5G could end up being 100 times faster than what we have now.

Instead of having a cell tower every few miles, - Woman: Yeah. - 5G requires that we literally need an antenna on every square block. Okay, hold on.

What really is 5G and why would it be so fast? Well, remember those radio waves? One of the major innovations of 5G is the ability to use higher frequency waves.

Because at higher frequencies, you can pack more information into each wave. Here's the catch. At higher frequencies, it's easier to block those waves.

I mean, visible light is very high frequency and I can block it with my hand. That's not a problem for fiber optic cables because they're basically long glass laser light tunnels. But 5G has to reach you wirelessly wherever you are, so that would mean they would need a lot more physical infrastructure.

Of course, new infrastructure costs money. Companies have the same incentives for where to put 5G that they had before. Cities, not rural areas, rich communities, not poor ones.

So 5G could be an exciting way to improve internet service for people who have fast access already. But the tech required means it's unlikely to help people who don't. At least not any time soon.

( music playing ) Cleo: We're here to see Loon, and what they do is they send balloons into the stratosphere to provide internet access to people below radio waves. Loon is a connectivity company that's really focused on the unconnected and the under-connected. Cleo: Loon is owned by Alphabet, which also owns Google and YouTube, who funded this show.

but Loon didn't have any say over our editorial. So, they can't actually launch a balloon today, because there was a huge storm yesterday, which kind of also goes to show how finicky a lot of this stuff is. But what you have to imagine is that there's a balloon in there and then it launches from that large red thing up into the sky, and it uses stratospheric winds to navigate to its next location, which could be on the other side of the world.

( music playing ) So, you can see a number of balloons over here in South America, and you can see what altitude they're at, like, at 60,000 feet, and basically where they're flying. ( music playing ) This is the hatchery. This is where we build and test all of our flight systems before they go out to launch.

- So this is the balloon. - This is the balloon. And then the part that flies with the balloon-- - It's this flight system here and the solar panels.

- Got it. And the brains of it are in that box. .

. - This box? - .

. . that's being cooled by those fans right now.

And so what we do is we put a ground station in a point of vantage where it can see the sky. And then from there, it can actually talk to one of our balloons. Our balloons can talk to each other and they're talking via radio waves.

And then from one of those balloons that's over the top of your phone, there's transmit and receive frequencies that are going down to your phone. What are some of the best examples that you've been most excited about where-- Yeah, when Hurricane Maria hit Puerto Rico and the Caribbean Islands, we were able to fly balloons over the top of Puerto Rico. And within a couple weeks, we were able to serve about a quarter million subscribers.

- Wow. - And it's enough to know that a user on the ground was able to get out a text message or an e-mail or a note to a loved one or something like that. ( music playing ) Amazon has Project Kupier and SpaceX has Starlink.

It seems like this is becoming something that more and more - companies are focusing on. - Yeah, absolutely. The more the merrier, because there's a lot of people to connect.

Cleo: These are all space or near space systems that use radio waves to get people access to the internet. And that's one reason why it's unlikely that they're gonna replace good old cables. Radio waves and laser light and all of these different types of technology that help us get access to the internet all in the end need to work together.

We don't seek to replace fiber or replace satellites. They're very complementary technologies. Going into space is still a new thing.

I'm pretty confident about my job prospects for at least the next while. The internet isn't a luxury. We don't just want to connect.

We need to to be a part of this massive, crucial, sometimes infuriating global community. So as you check the news or message a friend or watch a YouTube video, consider this, our connections have never been virtual. They're physical, and they're still very much a work in progress.

Hey. Want more episodes of "Glad You Asked"? You can find them here, and you can find more from YouTube Learning here.

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