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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

DNS Organizational (Generic) Top Level Domains and Authorities 1 2 3 4 DNS Second-Level and Lower Domains, Delegation of Registration Authority and Public Registration

Drawbacks of the Geopolitical TLDs

The geopolitical domains have been very popular for certain uses; for one thing, national governments and other “official” institutions like to use them, for obvious reasons. Typing “www.gov.XX” or “www.government.XX” where “XX” is a country code is likely to bring you to the national government Web site of most countries. Some companies and organizations use the ccTLDs because they allow them to choose a name already taken in the generic hierarchies, or simply to express national pride.

For many other companies and organizations, however, the generic TLDs have been much more popular than the country codes. I believe there are several reasons for this, but I think the most important one is that organizations are easier to locate using the generic domains.

Here's a good example of what I mean. In the town near where I live, a new grocery store called Aldi recently opened. I like the store and wanted to learn more about them, so I fired up my Web browser and sought out their Web site. Yes, I could have typed it into a search engine, but like most people I am lazy. It was much easier to just enter “www.aldi.com” into my browser, and lo and behold, up popped the web site of Aldi International.

Now, Aldi is actually headquartered in Germany, and they do have a web site at “www.aldi.de” as well. But I had no idea where they were originally from. I found them easily by going to “www.aldi.com”, because I didn't need to know their physical location, and because I know that most large companies have a “.COM” domain. Of course, being “findable” is very important, especially for commercial organizations trying to do business.

Another good example is the United States, which as mentioned above has its own country code, .US, in addition to dominating the generic TLDs. The authority in charge of this domain chose to make it follow a strict geographical hierarchy, so every domain must be of the form “organization.city.state-code.US”. So, to use this part of the name space, a company in Boston must be within the “.boston.ma.us” domain.

That's very neat and logical, but it makes names both longer and harder to guess than the generic equivalents. Suppose you wanted to get information on metals giant Alcoa. If you're in the industry you might know they are located in Pittsburgh, but if not, which is easier to find, “www.alcoa.pittsburgh.pa.us”, or “www.alcoa.com”? Anyone here know how to spell Albuquerque? J

It is for this reason that the .US domain achieved success in certain segments of society but not in others, especially commercial entities (corporations). The strict hierarchy does have some real advantages, however, such as avoiding name space conflicts. The .US authority eventually abandoned the strict geographical hierarchy due to its non-acceptance.

DNS Organizational (Generic) Top Level Domains and Authorities 1 2 3 4 DNS Second-Level and Lower Domains, Delegation of Registration Authority and Public Registration