How Do Web Site "Domain Names" Work?
What happens when you type www.web-site-address-dot-com into your browser?
Every website has two addresses. Each address directs your Internet browser
to display a specific web page, but they work in very different ways to get to
the same place. The first address is the original internet addressing plan,
called an IP address. They look like a string of numbers. ie: 184.108.40.206. The
most common Internet address we see is the
type of address. This address is called a domain name address.
To understand why every website has one of each, Lets go back to the beginnings of what was the internet, before it was THE INTERNET. Most people are aware that this thing we call the Internet was originally only a linking connection between computers on college campuses. Computer science departments all over the country were doing research. ( the United States military was funding much of this research, and doing some of it's own, but we�ll skip over that part for simplicity.) In those days long ago, computers were the "main frames" that filled whole rooms in the computer science buildings of college campuses. If you wanted to "log on", you walked across campus and sat down at a keyboard in the room with the computer. Because there was only one "computer" at each college campus, it was easy to remember the "address" of the computer you wanted to talk to on another campus. All the addresses were in a single printed directory book. It was not difficult to maintain an accurate list of addresses. As the number of computers grew, so did the directory. Remember that every website, every "mainframe" and every desktop computer has it�s own specific IP address. Imagine trying to keep your list up to date. Thousands and thousands of websites and computers are added to the Internet every day. How could you keep track of all those addresses? Update: In 2001, a major appliance manufacterer will announce a "web-enabled" refrigerator !! This was an early 2000s newsletters from the VectorInter.Net CTO. We've left it un-amended over the years, but you are probably reading this on a phone, tablet or other device, but probably NOT a refrigerator.
To understand IP and DNS addresses, Let�s use this analogy. Think of a city library. Every book in the library has an ISBN number, a unique identifying number that a "bar code" reader would identify as that specific book. This is the same reference number Barnes & Noble and Amazon.com use too. These books are your website in this example. This is important because the library system "knows" that the book you are searching for is "at the main branch downtown". Further, they would know it is located in the "business" section, under a sub-section called "computers", on a shelf called "VectorInter.Net". The third book from the end is called "Vector Newsletters" and contains this page. Obviously, a library system would have copies of the book in each branch, but you understand the concept in this limited example.
All pages on the internet are stored on special high-powered computers called servers. These are the library shelves of the internet. ( Read "How web site hosting works", in the VectorInter.Net Newsletter section of this web site.)
As the Internet grew, a new naming system evolved. It is called the Domain Name System, or just "DNS". As I mentioned above, a DNS address is the common "name address" we see as www.VectorInter.Net . It matches a "name" to the IP address the computer needs to find the web pages you want. The advantage to DNS addresses are many, but simply; they are easy for the non-technically inclined and the marketing departments to utilize. This is not a bad thing. It has contributed to the phenomenal growth of the Internet, Email, E-commerce and workplace productivity gains. Who among us is not aware of Ebay, Yahoo!, or Amazon.com? These words have become brand names or reinforce an existing identity, as in www.Sony.com . The parallel benefit is that the average computer user does not need to understand any of what we are discussing here.
We have reviewed a little history, so let�s go back to the original question, "How do domain names work?"
When you type in a website name into the address bar, and hit enter, the browser really has no idea what you want. The address is in the "wrong" form. A request for help is sent from your browser to the nearest local DNS server. Here is our high-tech directory assistance. The DNS server in your town, checks it�s list of names and finds that the name www.VectorInter.Net matches the IP address of 220.127.116.11, That information is returned to your browser, which immediately restates the request for the web pages using the IP address. The browser displays what you wanted to see. Simple, right? Of course not. This is "computer stuff" and nothing is that simple, but to understand the process, that�s close enough.
What if your web site is brand new? How would anyone find you? ( You can read "How search engine spiders and robots work", in the VectorInter.Net Newsletter archive.) Lets go thru the process again. If I am in your town and request the same web page, the DNS server remembers your request from yesterday. It matches the name/IP address connection with little effort, because it located the page the first time for your request. Every DNS server remembers prior address request. That is why your browser opens the homepage to @aol, or MSN, START, or ORANGE as quickly as is does. The DNS server knows the IP address. It doesn�t need to re-learn the name/IP address match each time.
What if we are requesting a brand new website, half the world away? How does the DSN server in your town know or learn a new website�s IP address? It does the same thing your browser did. It asks. Each DNS server can ask it's neighnors or a bigger DNS server in the next larger town. As an example, if the DNS server in Manchester, UK doesn�t know the matching IP Address of a web site it is looking for, it will ask London. If London doesn�t know, it will ask Munich and New York. This process continues until a website in the smallest town in the world is found. The information flows backward to New York or Munich and then to London and Manchester, With the correct IP address, so your browser can ask for that small town website, and it�s retrieved for viewing. Each DNS server along the way remembers the name/IP address match. If a web surfer in Cairo, Egypt wanted to view the same web page in the example from above, the desktop browser would ask the DNS server in Cairo, that machine would ask the DNS server in Rome. The request would jump from spot to spot until reaching Munich, Germany. Remember that Munich "knows" the name/IP address match. There is no need to go all the way to the web page again. The information flows backward to Rome, to Cairo, and to your new E-commerce customer in Al Jizah, a suburb of Cairo.
This whole process is call "propagation", and is the answer to our original question: "How Do Domain Names Work?" Propagation allows your web browser to locate any web page that is available on the world wide web. More importantly, this process allows any web browser to find your website
Read about how
"On-line Newsletters" can build your business or
to avoid bugs, worms and viruses."
Visit the VectorInter.Net newsletter archives on this web site.