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You ever walk through a modern shopping mall and just stop and wonder how it all works?

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You've got the digital signs, the public Wi-Fi, the cash registers in every single shop,

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all running smoothly. It feels like magic, right? Well, behind that seamless experience,

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there's this invisible, super complex web that makes it all possible.

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Today, we're going to pull back that curtain and actually design one of these networks from scratch.

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So let's really think about it. What does it take? I mean, beyond the actual stores,

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and the food court, what is the one single thing that a modern shopping center absolutely cannot

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survive without? You can't see it, you can't touch it, but if it goes down, the whole place grinds to

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a halt. You guessed it, it's the network. It's the mall's digital nervous system. It connects every

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single device. From the manager's laptop to the printers in the back of a shop, it lets them all

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talk to each other, share info, and get out to the big wide world of the internet. It really is the

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engine that runs the modern mall. Okay, so let's get our hands dirty. We're going to build this

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digital nervous system ourselves. And we're going to follow the blueprint of a final project from a

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digitalization course. So the mission is clear. Design a complete, working, and secure network

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for an entire shopping mall, starting with basically nothing but a list of what needs to

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get connected. And here's what we're working with. This is the scope of our challenge. We have to

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connect all of these different areas. You've got the public-facing spots like the 15 shops and a

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huge supermarket. Then you have the critical back office places like admin and the GM's office and

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even a private apartment for the caretaker. Every single one has its own unique needs.

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Now, before we plug a single thing in, we have to lay down some ground rules. Every device on

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our network, and I mean everything from a server to a printer, needs its own unique address. It's

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just like how every house on a street needs a number. We call this its IP address, and it's

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how all the devices find each other and talk.

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Okay, don't let this string of numbers scare you.

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The subnet mask, think of it like the zip code

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for our mall's private neighborhood.

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It's what tells every device how to know

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if a message is for someone local, inside the mall,

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or if it's long distance and needs to go out to the internet.

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It's what creates our safe, secure digital bubble.

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And to keep things from getting chaotic, we make a plan.

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It's kind of like city planning for our digital world.

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All the important infrastructure,

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the switches and routers, they get the low numbers.

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Then we group all the printers together,

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then the computers, then mobile devices.

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This kind of organization is gonna save us

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so many headaches later on

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when we have to manage this thing.

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Now in our little digital city,

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there are three addresses that are the absolute VIPs.

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First, you've got the gateway router at .250.

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That's our one and only secure door to the internet.

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Then there's the application server at .90.

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This is the central brain

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holding all the important mall data.

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And finally, the DNS server.

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Think of it as the internet's phone book.

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It translates names you can read, like google.com,

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into numbers the computers can read.

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So how do all these things actually connect?

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Well, there are basically two ways.

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You've got your wired connection,

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that's the super fast, super stable pipeline

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for our most important gear, like servers.

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Then you have Wi-Fi, which is all about flexibility

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for things that need to move around.

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The secret to a great network is knowing exactly

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which one to use and when, which is what we're about to see.

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All right, we've got the rules,

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we've got the addresses, we've got the connection types,

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it's time to look at the blueprint.

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Think of this as the master plan for the whole network.

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This map is gonna be our guide as we go on a virtual tour

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and bring this mall's digital nervous system to life,

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one room at a time.

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So we're gonna zoom right in.

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We'll look at the key areas of the mall,

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we'll place the hardware, we'll assign the connections,

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and we'll bring each and every space online.

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You ready?

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Let's go.

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Our first, and you could say most important stop

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is the administration office.

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This is the command center.

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It's the heart of the whole operation,

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where all the really critical data lives.

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Getting this part right is absolutely essential.

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And you can see our strategy in action right here.

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Look at what's plugged in with a wire,

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the application server, the desktop PCs,

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the big network printers.

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We need maximum speed and rock solid reliability here

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so they get a physical cable.

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The Wi-Fi router, that's there to give flexible access

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to anyone who might bring a laptop or phone into the office?

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OK, from the main admin hub, let's

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head down the hall to the general manager's office.

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The setup in here is a little bit different

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because it's tailored for just one user who has

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some pretty specific security needs.

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See the setup?

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The manager's laptop is wired right into the internet.

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That gives a secure, super stable connection

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to that central server.

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But check this out, the printer.

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It's a local printer.

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That means it's not on the network at all.

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It has no IP address.

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It's plugged directly into the laptop,

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which keeps any sensitive documents

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completely off the shared system.

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It's a simple but really effective security move.

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All right, now for the fun part.

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We are heading out onto the main mall floor

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to get the retail shops connected.

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And remember, the plan we're making here

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isn't just for one shop.

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It has to be a template that we can copy

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and paste 15 times over.

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So inside a typical shop,

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we've got a really smart mix of tech.

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Wi-Fi gives general internet access for the staff's devices.

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The main color printer is wired in for reliability,

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but a second black and white printer

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is on Wi-Fi for convenience.

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Now, here's the most important part.

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The chip and PIN machine, the one that takes card payments,

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it is not on our data network, no way.

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It uses a totally separate dedicated telephone line

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for maximum security, that's non-negotiable.

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Our last stop on the tour is the busiest place

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in the entire mall, the supermarket.

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It's got multiple checkout lanes, so the network here has to be tough, reliable, and totally secure.

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And at each of the five tills, you see the same pattern.

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The main till system can access the mall's internet to update sales data for management.

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But, just like in the smaller shops, the payment machines are on their own isolated phone lines.

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And the little receipt printer? That's local. It plugs right into the till itself.

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No network, no IP address needed. It's all about reducing risk where it matters most.

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So, we've toured all the individual rooms, we've connected all the devices, now it's

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time to zoom back out and see how this whole thing actually works together as one big system.

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How does a request from a shop actually get to the server and back again?

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Let's follow the data for a second.

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Let's say a shop computer needs the latest sales figures.

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That request flies through the air on Wi-Fi to a central switch.

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The switch acts like a traffic cop.

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It knows exactly where the application server lives, at address dot 90, and sends the request

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straight there.

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The server grabs the data and sends it right back.

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Now what if the manager wants to check a website?

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Their request goes to the gateway router, our door to the internet, which zips out,

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grabs the page, and brings it back.

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It's this constant high-speed dance of data happening every second.

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And there you have it.

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By following our blueprint, by applying that smart IP address plan, and by choosing the

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right connection type for every single device, we've designed a complete digital infrastructure.

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We have built the nervous system for a fully connected, intelligent, and totally operational

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shopping center.

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You know, it's pretty fitting that the original project instructions had this quote in them.

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Because in network design, just like in trying to explain it, order and clarity are everything.

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A well-structured plan is the difference between a system that just works and one that is a

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constant nightmare to manage.

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So the next time you're out and about, maybe you're in a hospital, an airport, at your

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school or even your office, just take a look around. Now that you've seen the blueprint for

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a mall's network, where else can you spot these invisible nervous systems quietly connecting and

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running the world all around you?