Domain Names

Categories: Information

“It took the night just to find the place.
A minor quirk in the navigation.
I’m so confused that I don’t know if we’re coming or going” – The Darkest of the Hillside Thickets

I ordered pizza the other night, and after about half an hour, got a call from the pizza driver. “I’m out front,” she said. I thought it was odd that she hadn’t rung the doorbell, but said, “OK, I’ll be at the door in a second,” and hung up. I then opened my door to see … no one. I waited a few seconds and then called the restaurant and explained what had happened. A minute later the driver called back. I opened the door and … still no one. I started asking questions like, “Where are you?”

“In front of your house.”

“No, I’m on my porch and I don’t see you.”

I started walking down my drive, looking up and down the street. Then I saw the car, parked in front of my neighbor’s house. I told the driver, “You’re at the wrong house.”

“Well, that’s where my GPS said to go.”

I paid for my pizza and went back inside, wondering about her future as a driver. Both my house and my neighbor’s house have numbers on them. That didn’t help her because she wasn’t looking at the numbers, just at what her GPS said.

The Internet is sometimes that way; we don’t always pay close attention to the websites we go to. Oh, we know the addresses of the ones we use all the time, but we may not always take a close look at links before we click them. Sometimes that’s just being too much in a hurry to take care, and sometimes it’s because we don’t really know what a Web address means.

Everybody knows an address begins with “www” and ends with “.com,” unless it’s “.edu” or “.org” or something else, right? Except sometimes an address doesn’t have a “www” in it. Why is that? Most people don’t know. In fact, the real addresses of the Web are IP addresses; each device (server, PC, tablet, smartphone, etc.) attached to the Internet has to have one. An IP (Internet protocol) address is a unique number to identify every device, so that your browser, email and other applications can find their way from one side of the Internet to another. The things we humans call addresses are URLs (uniform resource locators) and they’re part of the Domain Name System. The reason the system exists is that it would be incredibly difficult for us to remember the actual IP addresses (“Now let’s see, Google is 216.58.216.196, and OSU Mail is 139.78.99.99 …”); hence URLs.

The Domain Name System (DNS for short) defines how the URL looks based on a hierarchy. At the highest level are what are called top-level domains , which tell you what type of website you’re connecting to. This is the part that comes at the end of the URL: .com, .edu., .org and so on. Some of them describe what type of entity owns the address: .com for businesses, .org for non-business groups, .edu for universities, .mil for U.S. military. There are a lot of these. There are also two-letter TLDs that identify the country in which the domain is registered. You can see a full list of TLDs here: http://en.wikipedia.org/wiki/List_of_Internet_top-level_domains.

The next part of the address is the actual domain name, the part for which you have to register (and generally pay). The domain name is paired with a TLD for registration purposes, so registering “okstate.edu” is not the same as registering “okstate.com”; businesses and other organizations will often register as many of the most popular TLDs for their domain name as possible to help with branding and to avoid confusion.

The next parts of the URL are also important, although a working URL can have one, several or none of them. This is where (if it’s used) you can find the “www” in addresses; this part is intended to identify the actual server that is hosting the website or other Internet service (e.g., email). This section of the URL can be multiple names, which indicates a hierarchy of services within the domain, whether by a separate server, a virtual machine or some other method. So our support site, http://support.dasnr.okstate.edu shows that we are the DASNR support group at Oklahoma State University; the mail site, http://mail.okstate.edu is pretty obviously the mail server at OSU.

Using server names deceptively is also often a method used to trick people into thinking that they’re clicking on a good link when they’re not. If I want to scam people into giving me their bank account info, I can get more people to click my fake link if it points to something like “http://citibank.12.com” than if my URL reads “http://www.12.com.” Using a word that people expect to see in the URL makes it harder to spot the problem. It’s a good idea to scan the URLs of any links you’re planning to click pretty closely so you can spot any bogus links.