What are Domain Name Servers and DNS?

From January 2017 we are moving away from private name servers to an independent system that includes servers in multiple locations, inbuilt failover, improved speed and reliability.

If you own a domain name and a website using that domain name, then you’re using domain name servers and DNS. Here’s an overview of DNS, name servers, their relevance to your website and why we’re changing our name server setup.

  1. Why Are We Changing Name Servers?
  2. What is DNS?
  3. What is the Root Domain?
  4. What are Root Name Servers?
  5. Who is Responsible for the Domain Name System?
  6. What is a Name Server?
  7. How Does It All Work?

Why Are We Changing Name Servers?

From January 2017 we are using TPP Wholesale name servers for all domain names we manage through the registrar TPP Wholesale. The reasons for this are:

  • Servers in multiple locations
    TPP Wholesale’s DNS servers are located in multiple locations, including the US, Europe, Asia and Australia.
  • Servers use Anycast DNS
    TPP Wholesale’s DNS servers utilise Anycast DNS which allows for multiple, identical, global DNS servers using the same IP address to handle and direct requests to the closest location.

If your website visitors are physically distant from a DNS server they could experience slower load times. However, with Anycast DNS the request is routed to the server nearest to the visitor’s geographic location ensuring faster loading times for your website.

In addition to the faster loading times other features and benefits of using TPP name servers with Anycast DNS include:

  • Higher level of redundancy
    Anycast DNS service has inbuilt failover, so if a server should fail traffic is re-routed to another DNS server location without the end user noticing any problem. This also offers protection against any DDoS attacks.
  • Greater speed and availability
    There is usually additional cost incurred for Anycast DNS, but the service is included with all domain names held with the TPP Wholesale registrar.
  • Domain name zone administration
    Every domain name has its own administration panel for administering DNS records.

What is DNS?

The Domain Name System (DNS), in simple terms, is a phone book for the internet. It allows us to enter user-friendly domain names, such as wiseinternet.com.au, instead of a long list of numbers called IP addresses.

Before DNS was invented computers would connect via IP addresses, but the Domain Name System allows the attachment of domain names to these numbers so we can easily remember web addresses and websites.

The Domain Name System is the central database of the internet and without this system the internet would cease to operate as it now does.

What is the Root Domain?

At the top of the DNS hierarchy is the root domain. The root domain contains all the top-level domains of the internet, 1058 TLDs as of July 2015, This includes 730 generic top-level domains (gTLDs) and 301 country code top-level domains (ccTLDs).

The Internet Assigned Numbers Authority (IANA) is the manager of the root zone database. You can view the list of top level domains on their website at http://www.iana.org/domains/root/db.

What are Root Name Servers?

There are 13 root name servers that implement the root domain for the official global implementation of the Domain Name System. Originally there were 10 servers in the United States and one each in Stockholm, Amsterdam and Tokyo.

However, there are not just 13 physical servers. Each operator uses redundant computers to provide a reliable service and now, using anycast, the physical servers are located all around the world.

The 13 root name servers are operated by Verisign, USC-ISI, Cogent Communications, University of Maryland, NASA Ames Research Center, Internet Systems Consortium, Defense Information Systems Agency, US Army Research Lab, Netnod, RIPE NCC, ICANN and WIDE Project.

Who is Responsible for the Domain Name System?

An ICANN committee manages the root server system and root zone file. However, the root zone is controlled by the United States Department of Commerce and they must approve all changes to the root zone file requested by ICANN. ICANN’s bylaws assign authority over the operation of the root name servers of the Domain Name System to the DNS Root Server System Advisory Committee.

What is a Name Server?

A name server is a web server that has DNS software installed on it. Generally this server is managed by your website host and it is specifically designated for managing the domain names that are associated with all of the hosting provider’s websites.

Your website’s domain name is usually pointed to at least two name servers (e.g. ns1.wiseinternet.net and ns2.wiseinternet.net). When a user enters your website address into a web browser the domain name resolution process locates the name servers for your domain name which then finds the website address to load your website content for the user.

The entire process of querying DNS to find the address of your website can take less than a second. Therefore, the majority of your visitors will never be aware of the name servers you use for your site unless something goes wrong.

How Does It All Work?

When a user on a computer on the internet enters a domain name into their browser the domain name needs to be found. Resolving the domain name requires a domain lookup by breaking the domain name into it labels from right to left.

For the domain name wiseinternet.com.au the first component is “au” (au being the Top-Level Domain (TLD) for Australia). A query is sent to the root server to obtain the responsible authoritative server for “au”. AusRegistry is the official “au” domain name provider and further queries for each label of wiseinternet.com.au return more specific name servers until a name server returns the address of the wiseinternet.com.au website.

As domain name information does not change very often it is cached by intermediate name servers or by your own computer. Therefore complete DNS lookups to the root name servers are relatively infrequent.

The Process When You View a Website

Here’s the process if you visit www.yourwebsite.com:

  1. You type “www.yourwebsite.com” into your browser.
  2. Your browser uses DNS to look up the name servers for www.yourwebsite.com.
  3. The name servers ns1.hostingcompany.com and ns2.hostingcompany.com are retrieved.
  4. Your browser uses the name servers to look up the IP address for www.yourwebsite.com.
  5. Your browser gets the response: 203.89.228.137
  6. Your browser sends a request to 203.89.228.137, including a specific page if it’s not just the website’s domain being requested.
  7. The web server hosting your website sends the requested page to your browser.