This lesson will be about IP addresses. These are important because allow computers to communicate to one another.
This lesson will cover:
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Command Prompt
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Ipconfig
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IPv4 addresses
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NAT
Because they allow computers to communicate together, they are also used to track who is doing what. For example, if your doing something illegal like hacking into the CIA or something crazy, they can see your IP address and track that back to you. Then jail time.
But if someone is hacking you, you can work to uncover who may be attacking you or where they are located.
IPCONFIG
First, right click the start button or type into the Cortana bar cmd
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Cmd takes you to the windows command prompt. This is a powerful tool if you know what your doing. The command prompt is faster than a graphical user interface and can display more information if requested. This is what the starting school should look close to:
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Starting with some basic concepts, we are going to look at the Ip address. In the command prompt window type in Ipconfig. This command will take you to this screen. This has a lot of useful information when learning about computer networking.
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Just some background on this screen, this shows you all of the internet adapters that your computer has. These adapters allow you to connect to other computers and the internet. Towards the top you see Ethernet adapter Ethernet, this will give you more information if your computer is connected to the network with an Ethernet cable. In my case, I am connected to a school computer via Wi-Fi connection. You can see this midway through the page.
The main thing we are looking for is the IPv4 or IPv6, Subnet Mask and Default Gateway. You need all three of these to connect to the internet.
The Wi-Fi information shows a DNS suffix which just means the name of the connection. TIFFIN.LOCAL is the name of this network.
IPv4 and IPv6 Addresses are what the computer needs to access the internet. These can be given automatically from another source or they can be typed in manually. IPv4 is the most common today, my IPv4 is 10.101.15.73 which looks very simple compared to the IPv6 nonsense. IPv6 isn’t used much today but will be used in the future.
The Subnet Mask shows how many IP addresses can be on your network(complicated).
Finally, the Default Gateway (which is usually a router) is that next step from your computer to the internet.
The rest of the adapters like Virtual box or Bluetooth can also give useful information but its not necessary for this topic.
Another command to give more information is called Ipconfig /a. This is the same above but shows more important information.
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On this screen there are a couple of important pieces of information. The Physical Address for the wireless card is E4-A4-71-F7-77-95. This is important because that is specific to your computer, so if your doing something bad or illegal, this can get you caught. There are ways to alter it but this topic is for another day.
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WHATS MY IP
Now that you can see your IPv4 address, were going to talk about how that talks to the internet. But wait…, lets see what the internet sees our IP address as.
Go to Google
Type into the search bar, whats my Ip
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So, why is this different? My IPv4 address from that ipconfig command said my address was 10.101.15.73.
Network Address Translation (NAT)
Well the IPv4 address from ipconfig is a private IP address and the one from this website is a public one. This is due to a process called Network Address Translation(NAT) which changes a private address to a public.
