Understanding the Domain Name System

Understanding the Domain Name System Ever wonder why DNS systems came into existence? Efficiency. Every computer has a distinct IP address, and the Internet needed an elite method for obtaining these addresses and for managing the system as a whole. Enter ICANN.

The Internet Corporation for Assigned Names and Number manages the DNS root of the Internet domain namespace. ICANN’s role is to manage the assignment of identifiers, ensuring that all users have unique names.

The DNS system is run by a series of servers called DNS servers. ICANN manages the root DNS domains, under which are the top-level domains. It also manages:

Organizational domains
Geographical domains
Reverse domains

Beneath the top-level domains are other naming authorities such as Nominet, the UK’s naming authority.

How does a DNS Query work?

The process occurs in two parts. Firstly, a name query begins at a client computer and is passed to DNS client service for resolution. When the query cannot be resolved locally, DNS servers are queried.

For example, when a web browser calls the fully qualified domain name www.discountdomainsuk.com, the request is passed on to the DNS client service to resolve the name by using locally cached information. If the query is held in the cache, then the process is complete.

If, however, the query cannot be answered locally, the DNS client service uses a server list (ordered in sequence) to query external DNS servers. When a DNS server receives a query, it first checks to see if it is authoritive for that domain name. If it is authoritive, it resolves the name, and the process is complete.

If the DNS server is unable to resolve the query, it in turns queries other DNS servers, using a process known as recursion. DNS servers make use of root hints to assist in locating DNS servers, which are able to provide the required result. In this way, DNS queries are minimised and the Internet is able to operate quickly and effectively.

A typical query may run as follows:

Client contacts Nameserver A looking for www.discountdomainsuk.com.

Nameserver A checks its cache, but can’t answer, so it queries a server authoritive for the Internet root.

The root server responds with a referral to a server authoritive for the .com domains. NameserverA queries the the .com server and gets referred to the server authoritive for www.discountdomainsuk.com.

Nameserver A queries this server and gets the IP address for www.discountdomainsuk.com.

Nameserver A replies to the client with the IP address.

Queries can return answers that are authoritive, positive, negative or referral in nature. In the event of a negative answer, another DNS server is queried.

Understanding the Relationship Between Domain Names and Hosting
Selecting a domain name can be a bit overwhelming since domain registrars often offer far more services than just domain names. Many offer hosting as well, so it helps to understand the relationship between domain names and hosting. Domain names and hosting are two completely separate products, .....
What Is a Domain Name?
Imagine life without the internet? No - everything these days is governed by its presence, so it is important that everyone has at least a basic understanding of the key to all this activity - Domain Names.
How Internet Domain Names and DNS Relate With Each Other
It is a complex world, millions of domain names and thousands of internet users!
Domains: Your Friendly Address on the Internet
Would you believe that there was a time that the internet didnt have any domain names? During those days the internet was very much like a telephone network. If you wanted to visit a site, you would have to type that site IP address. And without domain names, visiting other websites became a chore....
Where You Should Register Your Domain Name
If you own a website, you would understand the cost and effort required to make everything just perfect. No one wants to invest a lot into a web site and just turn it over to anyone. You need to make sure the domain registrar you choose is professional and can do the job right.
Domain Name Renewal Woes
Here are some helpful tips to ensure that your domain name stays right where it needs to be - in your domain name account!
Ideal procedure of Transferring Domains
In the modern times conducting business on the internet has become a common practice. Why is it so? It has become a common practice as a person can earn money without any hassle of going to the office or employing a large...
Domain Goldrush Part 7 - WLS Gets ICANN Approval
After a long delay, ICANN recently approved the introduction of VeriSigns Wait Listing Service (WLS). For those of you not familiar with WLS, it is a registry-level first-come first-served subscription service for the automatic registration of deleted domain names. It is largely based on SnapN...
What is a domain name?
The domain name is a unique name that identifies a web site. All domain names have 2 or more parts and are organized hierarchically with the more generic parts to the right. The domain hierarchy is presented by dots found in the domain name...
Domain Names-Protect Yours From Drop Catchers
Imagine youre the owner of a successful Web site, but when you logon one day all you get is an error message. Or worse yet, the domain name now points to a site full of advertisements. Thats right. Youre out of business.