Please Whitelist This Site?

I know everyone hates ads. But please understand that I am providing premium content for free that takes hundreds of hours of time to research and write. I don't want to go to a pay-only model like some sites, but when more and more people block ads, I end up working for free. And I have a family to support, just like you. :)

If you like The TCP/IP Guide, please consider the download version. It's priced very economically and you can read all of it in a convenient format without ads.

If you want to use this site for free, I'd be grateful if you could add the site to the whitelist for Adblock. To do so, just open the Adblock menu and select "Disable on tcpipguide.com". Or go to the Tools menu and select "Adblock Plus Preferences...". Then click "Add Filter..." at the bottom, and add this string: "@@||tcpipguide.com^$document". Then just click OK.

Thanks for your understanding!

Sincerely, Charles Kozierok
Author and Publisher, The TCP/IP Guide


NOTE: Using software to mass-download the site degrades the server and is prohibited.
If you want to read The TCP/IP Guide offline, please consider licensing it. Thank you.

The Book is Here... and Now On Sale!

Get The TCP/IP Guide for your own computer.
The TCP/IP Guide

Custom Search







Table Of Contents  The TCP/IP Guide
 9  TCP/IP Application Layer Protocols, Services and Applications (OSI Layers 5, 6 and 7)
      9  Name Systems and TCP/IP Name Registration and Name Resolution
           9  TCP/IP Name Systems: Host Tables and Domain Name System (DNS)
                9  TCP/IP Domain Name System (DNS)
                     9  DNS Name Registration, Public Administration, Zones and Authorities

Previous Topic/Section
DNS Hierarchical Authority Structure and the Distributed Name Database
Previous Page
Pages in Current Topic/Section
1
2
34
Next Page
DNS Geopolitical (Country Code) Top Level Domains and Authorities
Next Topic/Section

DNS Organizational (Generic) Top Level Domains and Authorities
(Page 2 of 4)

Original Generic TLDs

The initial deployment of DNS featured a set of seven top-level domains that are in the standard called generic TLDs. The idea was that each company or organization could choose a name within one of these TLDs; they were “generic” enough that every organization would find a place that suited them. I prefer to call them organizational, because they divide the generic portion of the name space by organization type. The initial TLDs and their original intended organization types were:

  • .ARPA: A temporary domain used many years ago for transition to DNS. Its name refers to the ARPAnet, the precursor of the modern Internet (in turn named for the United States Defense Advanced Research Projects Agency, ARPA). Today this domain is used for reverse name resolution.

  • .COM: Corporations and businesses.

  • .EDU: Universities and other educational organizations.

  • .GOV: Government agencies.

  • .MIL: Military organizations.

  • .NET: Organizations that implement, deal with or manage networking technologies and/or the Internet.

  • .ORG: Other organizations that don't fit into any of the classifications above.

At first glance this seems like a reasonable way to cover the organizations of the world. However, since the .ARPA domain is “temporary”, this left only six categories for all other organizations. Also, the TLDs weren't all used as was originally foreseen; for example, the .GOV and .MIL domains were not used for all types of government and military organizations, but primarily for the United States federal government and military. .EDU ended up being used only for universities, again in the United States.

This left only three common top-level domains—.COM, .NET and .ORG—for almost all other groups and companies that wanted to use the organizational hierarchy. Since there were only three such TLDs, they quickly became very “crowded”, especially the .COM domain. A new fourth domain, .INT for international organizations, was added fairly soon to the original seven, but it too was only for a small number of organizations, such as international standards bodies. Despite the handful of organizational TLDs, there is no doubt that they have been much more popular than the geopolitical ones. I explain some of the reasons for this in the next topic.


Previous Topic/Section
DNS Hierarchical Authority Structure and the Distributed Name Database
Previous Page
Pages in Current Topic/Section
1
2
34
Next Page
DNS Geopolitical (Country Code) Top Level Domains and Authorities
Next Topic/Section

If you find The TCP/IP Guide useful, please consider making a small Paypal donation to help the site, using one of the buttons below. You can also donate a custom amount using the far right button (not less than $1 please, or PayPal gets most/all of your money!) In lieu of a larger donation, you may wish to consider purchasing a download license of The TCP/IP Guide. Thanks for your support!
Donate $2
Donate $5
Donate $10
Donate $20
Donate $30
Donate: $



Home - Table Of Contents - Contact Us

The TCP/IP Guide (http://www.TCPIPGuide.com)
Version 3.0 - Version Date: September 20, 2005

© Copyright 2001-2005 Charles M. Kozierok. All Rights Reserved.
Not responsible for any loss resulting from the use of this site.