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Now before we start talking about networking you need to have a basic understanding on how networks

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work.

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Now we all know that a network usually contains a number of clients connected to each other.

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Clients usually connect to a network an order to share data or share a resource.

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A really good example of a resource that we all have connected to networks in order to access is the

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Internet so we connect to why five networks and even wired networks all the time just to access the

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Internet.

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Now all networks whether it's wife Y or wired work on the same principle they have a device that is

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considered a server.

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Now in many cases for example in your home network this server is your outer.

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This is also referred to as an access point.

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Now this writer or a server or access point is the only device that has access to the source.

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So none of these clients have direct access to the resources even after connecting to the network.

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The only way they can access the resource is through the access point.

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So let's say for example you're a client number one and you're connected to your home network over a

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wife or over their net over a cable.

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And then you opened your browser and you typed Google dot com.

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What happens is your computer will send a request to the access point asking for Google dot com.

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The access point has access to the resaw is which is the Internet.

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In this example.

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So it's going to go and look for Google dot com.

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It will receive Google dot com and it'll forward that response to your computer.

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And as a result you will see the Web site loading on your browser.

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So if you actually go to your outer at home and look at it you'll see this bike.

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It's connected through a cable to the wall.

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And this is how it's getting its Internet access.

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Therefore it is the only device in your network that has direct access to the resource.

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And none of your computer is none of the computer is connected to the network can't access the source

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or can't access the internet without the router without the access point.

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So the only way for all of the connected clients to access the resource is to go through their outer.

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No the data tries varied between the clients and the access point packets.

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So you could think of all of these arrows as a series of packets being transmitted between the client

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and thereafter as requests and responses.

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Now in Wife I networks these packets are transmitted in the air.

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Therefore if you have a wireless card and you're within range you'll be able to capture all of these

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requests and responses.

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So basically you'll be able to see anything that any computer connected to the same network as you does

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on the internet because you will have to send all of this data through the access point.

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And because they're sending data in the area because you're in a wife network you'll basically be able

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to capture these requests and the responses and you'll be able to see that you are.

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LS they visit the user names the passwords they enter the chat messages anything they do on the Internet

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will be sent us packets.

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And therefore you'll be able to capture it and analyze it.

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We'll talk more about that and more about how networks work as we go through the course.

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This is enough to get you going through the next few lectures so that you can sniff to analyze it and

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start launching some cool free connection tags.