Original subtitles

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Before we can start trying to hack into networks and break into them.

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There's a few basics that we need to learn before we can do that.

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So basically what is a network and that's what it is just a number of devices connected together.

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They are connected together for a reason so that they can share data.

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This data can be files can be resources.

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It can be for example your home network.

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Usually you use it to just access the Internet which is you can look at it as a resource or as a source

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of data.

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So all networks Wi-Fi or wired achieve this sharing of data using the same principle and that principle

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is you need a device that acts as a server and then all devices communicate with the server so the server

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has access to the resource and all the other devices on the network that are connected to the server.

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Obviously they can access the data from the server so most Wi-Fi networks the server is the router and

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all devices connect to this router and they access the Internet through the router.

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So all the devices on the network have no access to the Internet as we can see in this diagram.

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The only device in the network that is connected to the Internet is the Wi-Fi router.

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All the other devices as we can see here we have client One and Two and Three.

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They have no access to the Internet but they can access it by connecting to the router.

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So whenever client three for example if it wants to open Google does come is going to send the request

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to the router asking is OK I need google.com.

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The router is going to go to the Internet.

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Its going to grab Google dot com and then forward this back to Client Number three supplies number three

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does not have direct access to the Internet.

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It has to go through the router and the router is going to bring the request and send the response back

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to client number 3.

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Now all of this data requests and responses are transferred or transferred through back packets.

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So you can imagine all these arrows are a number of packets being sent between the clients and the router

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and involve Wi-Fi networks these packets are sent into the air.

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So are broadcasted.

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And if you're if you're within range with these pockets then you can just sniff them capture them and

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read them and you'll you'll be able to see the information in there.

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So all this data.

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So whether it's user names passwords videos audio music charts all of that is transferred as packets.

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And it's always transferred between the client and the router because the client has no access to the

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Internet.

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So if you capture these packets you'll be able to see all of this data transfer and you'll be able to

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see all these passwords usernames emails videos all that you'll be able to capture it and read it on

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your device.