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Hello and welcome. My name is Keith Barker. And most of the time in our

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internal networks,

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we're going to be running private IP address spaces, stuff like the 10 network

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or 1.72,

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16 through 31 or 192.168. Anything. And if we are, that's great. However,

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those clients are not going to be able to get out to the internet because when

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internet service

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providers see those source IP addresses, they're going to say, "Ain't sorry,

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you shall not pass."

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Or if we have somebody trying to send a packet to a destination, that's a

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private RFC-19.8

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address. Once again, the service provider network is going to say, "No, but we
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address. Once again, the service provider network is going to say, "No, but we

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don't have any clue

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where exactly that lives and it's going to go ahead and drop it." So how do we

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solve that? The

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answer is we lie. We take IP addresses, whether source or destination, and we

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modify them so that

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we replace them with the appropriate IP address. When we swap out the source IP

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address on the

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initial flow of traffic, it's called source NAT. If we're swapping out on the

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initial flow of

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traffic, the destination address is called destination NAT. So here's what you

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and I get to do in these
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and I get to do in these

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videos. We're going to take a look at the basic concepts of NAT, including some

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of that terminology

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to make sure we're clear why we would use one type of NAT over another, and

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then we'll put a game

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plan together for the implementation of address translation. And then third, we

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'll actually configure

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and verify address translation, both source and destination address translation

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. So if you're

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ready. I'm ready. I'll see you in the very next video.