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Let us start learning domain name system.

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In this lecture, what is a domain will learn what is Nien system and what is DNS?

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To identify hosts, IP addresses are cumbersome for humans to use and to remember the Internet supports

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the use of host names to identify hosts, both clients and servers.

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In order to be used, the protocols such as TCP IP host names, are converted into IP addresses using

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a process known as name resolution.

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There are different forms of name resolution in the Internet, but the most prevalent and the most important

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one uses a distributed database system known as the domain name system.

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Basically, domain name system converts human readable domains like www.youtube.com into IP addresses.

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So let us have a quick example, I would like to ask you one question.

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Is it easy to remember your friend's phone number or his name?

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Right.

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It's easier to remember a name rather than a phone number.

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DNS, the distributor, claims of a networked database used by DCPI applications to match between hosts

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and IP addresses and also viceversa the DNS provides the control that allows clients and servers to

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communicate with each other and also a protocol for allowing servers to exchange information.

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As you can see, this is the main route, so let us consider a website admin, not Stanford dot edu.

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OK, so Dot Edu is the domain name of that particular Web site.

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And dot you to you, there can be any number of college domains, for example, the Stanford, Harvard

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and MIT L.M..

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That is the root level dot edu is a root level root authority, then comes Stanford or the Stanford

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stands for the domain name authority.

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Stanford is specific doping and finally the admin that is admin dot Stanford dot edu is a sub domain.

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So is it.

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It is easier to remember admit that Stanford dot edu than to remember an entire IP address.

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Let us have a quick recap.

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From an application point of view, access to the DNS is through an application library called Resolver.

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And Dennis makes it easier to remember the website's name rather than the IP address.

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In the next lecture, you will see in detail what is the name resolution process and how Direness performs

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name resolution.