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In the previous video, we already learn about
the concept of nat.

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Now in this video, we are going to learn how to configure nat. Let’s just start.

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But before configuring nat, first, we need
to configure default route.

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What is that?

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Actually default route is a static route,
but the destination will be all network.

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So for example, from router 2 want to go to
google, if we configure static route,

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the destination network will be 172.16.10.0/24,

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but if we configure default route, the network
will be all network, which is 0.0.0.0/0, usually

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default route is configured on the customer
router to internet.

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Because in the internet, the network is very
much.

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There is impossible to add static routing
to each network one by one, for example in

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the internet there is a network of google,
facebook, youtube, twitter, Instagram, and

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others.

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So once again, this is impossible to add static
routing one by one to specific network.

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This is why we will configure default route.

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Let’s just start, let’s see the routing
table first, do show ip route, here we can

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see that we don’t have a route to go to
google yet.

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Now let’s configure default route, configure
terminal, ip route and then the destination

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network is all network, which is 0.0.0.0 and
then the subnetmask is 0.0.0.0,

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And then the next hop is the ISP, which is
10.20.20.1

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Okay we have done, now router3 should be able
to communicate with google, let’s try, do

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ping 172.16.10.2, okay here we can see that
this is success.

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But from the client, the ping should be failed.

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Let’s try, okay this is failed.

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Remember that we need to configure nat on
the customer router so all client will able

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to ping to internet or google.

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I think enough for this video, in the next
video, we are going to configure nat, so all

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client will able to ping to the internet.

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Thank you for watching and see you on the
next video .