What is a Domain and its position in the network Hieraerchy

Forever I've been playing around with this operating
system, associated software and hardware, adding,
installing repairing, deleteing, reinstalling,
configuring, reconfiguring, and overall just breaking it
and putting it back together again with upgrades.
I have a question or questions if anyone can please be of
assistance. I cannot figure out, or just grasp, the
concept of a domain and the structure of the internet and
what a domain lies in hirearchael structure of it. I mean
I just cant do the things I want and I cant set up a
network until I grasp this concept.

What you are asking would be best answered by doing some reading & research,
as the answer is not a simple statement.

I'll try to give you some of the major points:

The Internet is the term used to represent the global network of networks.
It's the physical intrastate that makes it possible for me to post this
message in a place (a server) that you can retrieve it from. There are just
a handful of very powerful supercomputers that all Internet traffic
throughout the whole world pass through. These machines are collectively
called the "Backbone" of the Internet.

The World Wide Web and the Internet are not the same thing (many people
believe they are). The World Wide Web (WWW) is the term used to describe
the part of the Internet that provides information via web pages, web sites
and web servers. For example, this newsgroup exists on the Internet, but
not the WWW because there is no web server, no web site and no web page
involved. Newsgroups such as this one use another part of the Internet's
infrastructure called the UseNet. Email is another example of a different
kind of communication using the Internet as the conduit. Email is not part
of the WWW or UseNet.

If someone wishes to create a web site and "plug it in" to the Internet,
they would need to secure a unique "Domain Name" so that we don't wind up
with more than one site using the same name. Just like you have to go to
one of the many phone companies to get a number (you can't just decide what
your phone number is), you have to go to one of many Domain Registrars to
find out if the desired name is available and, if it is, register it to you.
There are a few "Top Level Domains" such as .com, .edu., .gov, .mil, .org
and .net. When you register a domain name, you first pick what top level
domain you would like and then a second level domain name within the top
level domain (i.e. cnn.com).

New domains are popping up all the time (.cc., .us, .per, etc.) but these
are not considered to be part of the original "Top Level Domains". So, if
you registered JoeSchmoe.org, your domain would be JoeSchmoe in the top
level domain .org. You would have exclusive rights to that name and
whatever content is associated with it, it is your DOMAIN (i.e. kingdom!).

When a new domain is created, old ones expire or change hands or change
machines on which they are being hosted, the record for that domain must be
updated and placed into a global database so that everyone on the planet can
know what domains are out there and where to find their content. This
global database is called the "Domain Name System" or DNS. Every Internet
Service Provider (ISP) keeps a copy of this database and they are constantly
updating it to make sure it is current. If you use, say AOL as your ISP,
then every time you open your browser and type in a web address you'd like
to browse, the request first goes to AOL's DNS Server and it looks up the
domain name you typed into your browser. If the domain name (web site) is
in the database, there will be a number (called an Internet Protocol or IP
Address) that indicates what particular computer that is physically
connected to the Internet the web site resides on. IP Addresses are 4 sets
of numbers separated by a period (i.e. 123.123.123.123) and the number that
represents the web site you originally typed into your browser is sent back
to you. Your computer can then send a message out which, in effect, says
"Is site: 123.123.123.123 out there anywhere?". The computer associated
with that number will respond and the connection to the web server for that
site can be made.

Now, the term Domain has another meaning as well. On a private network,
usually at a business, there should be only certain people who are allowed
to "log in" to the company's internal computer network. For each allowed
user, there is a user account created on a master computer for the company,
called the Domain Server. When you sit down and put your user name and
password into the log in dialog, the user name and password are sent to the
Domain Server and the credentials you entered are verified against those in
the user database. If the information matches, your computer is granted
access to the company network. Different users can have different levels of
access though. The President of the company can get to financial and legal
information that a data entry person couldn't get to because the President
has a higher level of access associated with her/his user account.

Private domains do not have to register their domain name as a public domain
would and the use of those top level domains are omitted here. So a private
domain name can just be made up and there may very well be duplicate private
domain names out there. It's not a problem though, because you have to be an
approved user of the domain to get in. An example of a private domain might
be: WidgetsRUs (note the absence of .com, .org, etc.).

Private networks come in all different shapes, sizes and configurations
(much more than I can get into here).

I hope this gives you the basic concepts, but as I said before, this is the
tip of the iceberg, so go get a book and dive in!

-Scott M.

"Tyson" wrote in message
...
Forever I've been playing around with this operating
system, associated software and hardware, adding,
installing repairing, deleteing, reinstalling,
configuring, reconfiguring, and overall just breaking it
and putting it back together again with upgrades.
I have a question or questions if anyone can please be of
assistance. I cannot figure out, or just grasp, the
concept of a domain and the structure of the internet and
what a domain lies in hirearchael structure of it. I mean
I just cant do the things I want and I cant set up a
network until I grasp this concept.

What exactly is it that you're curious about?...DNS?