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- In this video, we are going
to talk about networking.

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So in the end, it's all
about the internet, right?

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Let's say that this thing here,

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cloud-like shape is the internet.

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Everybody wants to go to the internet

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and in order to go to the internet,

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well, you need a router to be
taking care of the connection.

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The router is a device

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in a network that exists
on your local network

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and behind the router,
there is your local network.

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Let me use a different
color for the local network.

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And this local network,
maybe a simple network,

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where your nodes are
connected to directly.

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A node is any device
that has an IP address

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and it can look like this.

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A local network might also be
a little bit more complicated

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where another router is involved,

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and where another network is connecting

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with nodes by themselves as well.

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Now, on these nodes, you
need your IP configuration.

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IP, the internet protocol.

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It's the default protocol
that you are going to use

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to get to the network.

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Now, what exactly do we need?

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Well, let's say that we
are configuring this node.

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And on this node you
would need an IP address.

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The IP address would look

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like 192.168.1.12/24, for instance.

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The /24 in the IP address is an identifier

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of the part of the IP address
that is used for the network.

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So /24 means that the first three digits

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of the IP address are
used for the network.

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And that means that you
can say that this node

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is on the network 192.168.1.0/24.

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And it would also mean that
this node and this node

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have an IP address that
starts also with 192.168.1,

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followed by anything.

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The next thing that you would need

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in your node configuration is
the IP address of the router.

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So this router here is
identified as well 192.168.1.254,

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for instance, very often the router

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is using the last IP
address that is available

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in the byte, 254 is commonly used.

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You might see one as well,
that's the default route

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or the default gateway
that you need to configure.

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And the last part that plays a role

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is the DNS configuration.

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Now, what is DNS?

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DNS is about domain name resolution.

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It's about using names
instead of IP addresses.

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And if you don't have a DNS server,

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you can still communicate
to nodes on the internet

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but you would need to know the
IP addresses of all of them.

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That's not doable.

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And that is why you would
typically provide the IP address

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of a DNS name server as well.

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And if that is working successfully,

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you can get access to everybody
on the entire internet.