Every internet user makes use of the Domain Name System or DNS. However, very few people are actually aware of this important domain mapping mechanism. It is the Domain Name System that binds your URL or Uniform Resource Locator address to the right server on the internet. For example, if you type ABC.com in your browser’s address bar, the DNS system will bind this text to the corresponding web server on the World Wide Web. In the absence of this system, you will have to remember long IP addresses of website servers. Even memorizing one or two direct addresses (IP addresses containing several digits) of popular websites like Google or Amazon can be a challenging job for anyone! Read on to learn more on how this system works.
Basics of the Domain Name System
DNS is not located at one point in the world. In fact, it is distributed throughout the World Wide Web. There are a large number of authoritative servers all over the world that offer address translation services to various systems. Each authoritative system provides such translation capabilities to a set of systems within its domain. These authoritative servers gather information from root servers on the internet. Information about various domains on the internet is continuously updated.
The Domain Name System and You
Your computer’s operating system looks up the domain name entered in a browser’s address bar in its previous records. Generally, these previously stored records are known as domain cache. The operating system connects the browser to the required web server if an associated address is found in these records. If not, a request is forwarded to a DNS server.
Your DNS server is defined by an internet services provider. The DNS server searches its own records to find the exact address of the domain name requested by your computer’s operating system. If the local DNS server fails to locate the address, this request is forwarded to another server higher in the hierarchy. The process of forwarding requests or returning addresses will continue until the address is found or an error is returned.
The domain name mapping is not a simple process. Internet Protocol (IP) addresses and addresses may or may not have a unique one to one association. In many cases, a single IP address hosts a multiple websites or vice-versa. Usually, web hosting websites have multiple websites pointing to the same IP addresses. This arrangement permits web hosting companies to host a large number of virtual hosts on a single IP.
On the other hand, popular websites have the opposite requirement. Popular websites like Amazon or Facebook have multiple IPs pointing to the same website. It helps them to deal with excessively large traffic volumes. Also, popular websites ensure 100% uptime by using this technique. Billions of people across the globe use the DNS system every day and it is no doubt one of the most important components that work behind-the-scene in the World Wide Web.