So if you're going to a site on the Internet and you put in, say, www dot failed normal dot com, Or possibly, if your company organization has failed normal dot com and you're trying to access your email service is you might go to mail dot fail normal dot com.

Or, if you're trying to access some kind of file service's, you might go to ftp dot fail normal dot com failed.

Normal is the domain name.

The first part before that first period is the sub domain.

So W W W e mail or male ftp VPN.

So on and so forth.

So what sub domains are used for?

Is there a there?

A way to give your users one coherent naming strategy in order to access the Internet or the network service is that your company is providing.

So what you can do is for the website www dot feel normal dot com can point to a specific Web server.

Mail dot fail normal dot com can point to your e mail server.

Ftp dot Feel normal dot com can point to your FTP server.

Let's say you want to give VP and access to your users.

You can then set up a sub domain VPN dot fail normal dot com.

And so, if people want your people in your organization, want access.

The VPN service is they would plug that in for the address and then plug in their user name and their credentials in order to log into that VP and service.

So one of important things to understand about sub domains is that sub domains do not have to point to the same servers.

This is a way to give your users a coherent naming strategy, but on the back end, it can point to a lot of different places.

So let's say you have a website and you also have a human resource is portal.

So let's say you want your employees to be able to see how many vacation hours they've accrued be able to request vacation time, see what their insurance policy is that type of thing.

Well, what you can do is you can have w w w dot fail normal dot com that will point to your normal website, so that will go to your normal Web server and whatever is on your normal website will be there, but then you can have h r dot fail normal dot com, and you can have that pointed to some kind of Oracle portal.

And that will be your human resource is portal for people to be able to access their employment records or anything like that.

So it's important.

Understand that sub domains absolutely do not have to point to the same service now, many times in the real world, if your network is set up poorly or you don't have a lot of money, your email server and your Web server and your FTP server and your VPN service special in a Microsoft World may all reside on the same server.

But it's important to understand that they don't have to, so you can have an Oracle portal that's a completely different server completely somewhere else versus where your Web server is the email so on and so forth.

The other nice thing with sub domains is you can point Subbed remains either at i P addresses using something called a record, we'll talk about later, or two other domain names using what are called C name records.

So let's say.

For fail normal dot com we have a Web server that provides the Web service is fail normal dot com.

But then we have an email server, and we decided to use Google maps.

Will you sit there and you think about it?

And you want to make it easy for your users to be able to access the mail server with a naming strategy that they'll understand.

So what you can do is you can have www dot feel normal dot com.

Www.

We'll pull it to an I P address so you actually own your Web server?

You know what its I P addresses, So you will point www dot www toothy i p address.

On the other hand, for male not feel normal dot com, you're going to be purchasing a service from Google or maybe from Microsoft Ease and their outlook.

3 65 Something like that.

Then what you can do is you can have mail a dot fail normal dot com, and that would point to a domain name, so that would then point to, you know, email service is dot google dot com or something like that.

So that's one of the nice things about this is using this one kind of domain name strategy you can point to.

Many different service is many different servers, whether it's an I P addresses in an a record, whether it's an actual domain name using a C name record, you can point to all of these different things.

You can have one nice naming strategy.

It makes life a lot easier for your users.

And so that's what a sub domain is, and that's why it's important.