Original subtitles

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Hey they're welcome back.

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All right if you thought so far everything's been really really cool.

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Well, things are gonna get a lot cooler.

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We're going to be talking about the Internet backbone.

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So we recognize this because I've been talking about it for the last couple of lessons.

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But some of you may have had a question that is what do the arrows mean.

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I mean it's kind of like magic right.

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I just told you that we send off the IP address to the servers the server responds with some files but

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this is just magic like what do these arrows mean? So, we're going to talk about that in this lesson.

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And we're going to do that with this really, really fuzzy diagram that I found online from this website.

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It's not the clearest picture but it actually has some really important things so I want to use that

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to demonstrate to you what the Internet backbone is.

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So, as some of you know the way we connect in our homes, at a coffee shop, or at work is we usually have

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Wi-Fi or you know maybe sometimes we still have people they are using Ethernet cables

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and connecting through those.

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But for now let's just focus on the fact that we have a home and we have Wi-Fi and this Wi-Fi essentially

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gives us Internet from the router.

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You can see this little person over here working hard with a router next to him and this router is connected

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all the way to something called a modem.

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And this is something that if you ever sign up for Internet or change providers you most likely had

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somebody come to your house and install something.

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And that's this box over here that essentially allows the ISP the Internet

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Service Provider, this big building over here,

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we remember that, to connect to it.

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So this modem has the signal towers that transmit signals of,

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you know Google.com and it receives these messages and then this is why I picked this image just

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because I think it's incredible you see this wire that is connected all the way to the ISP and then

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the Internet Service Provider, the ISP is connected to this magical blue cable that is the Internet backbone

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and something that's really important in this image is the fact that there's Wi-Fi which is over the

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air but at the end of the day everything is kind of connected through cables.

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So some of you or many of you, or all of you might be wondering

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"What the hell is this Internet backbone thing?"

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Sounds cool. But this - this is kind of vague, so I found a really, really cool - cool thing that we can do together

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I'll post this website in the notes after this lesson.

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But if you go over here you actually see the Internet backbone. So, let's say we're in Brazil and we want

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to search Google.com.

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Well from Brazil, from our home, through Wi-Fi, it connects to our router, to our modem and then all the way

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to our Internet Service Provider lets say (the) Internet service provider is over here and then, through

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cables it connects all the way to, let's say this point over here, and let's say, for now that the Google

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servers are located somewhere in Portugal over here.

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Well that signal of me looking for that IP address of Google and looking for those Google files is going

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to go through this submarine cable.

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Yeah, you heard that right.

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It's a physical cable that goes at the bottom of the sea floor from Brazil all the way to Portugal where

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the Google servers are.

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And then the Google server says yep I got those files here there are and sends it all the way back.

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Through the ISP all the way back to our house.

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Isn't that cool that there's physical cables that are connecting, and creating the Internet so you know

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there are times where somebody destroys or something happens where these cable connections are cut off

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and you sometimes lose internet connection that way.

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But yeah the Internet backbone is literally just this network all over the world of connected cables

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so that we can transfer these files all over the world.

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And just to show you how insane this is somebody from the Opte Project over here - I got this off of Wikipedia,

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mapped out, and I believe this was in 2015, just 30 percent of the network, and you can see over here that

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each one of these dots is an IP address.

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So, a computer that is connected to another computer, that is connected to another computer.

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And that's the Internet.

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The Internet is just all these connected computers that are just transferring files between each other

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and as web developers and this is the coolest thing.

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And that's why I just think everybody should be a web developer because it's so cool.

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You're allowing this to happen.

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You're allowing this transferring of files from one computer to another, transferring knowledge from

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Brazil to Portugal and all over the world and you get to be part of it - you get to be part of this networking

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and get to evolve.

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When this picture of the Internet came to me I knew that this was the career for me.

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So, hopefully that gets you excited in the next session.

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I'm going to show you something really cool.

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Traceroute before we finish up the lesson and we get into the next sections so hope that was cool see

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in the next one.