Domain Name System (DNS)

The domain name system (DNS) is a naming database in which internet domain names are located and translated into internet protocol (IP) addresses. The domain name system maps the name people use to locate a website to the IP address that a computer uses to locate a website. Domain name system (DNS) is the system that is used to translate human-memorable domain names like ‘’ and host-names like ‘’ into the corresponding numeric Internet Protocol (IP) addresses as well as to identify and locate computer systems and resources on the Internet.

When you use an alphanumeric address like “” your computer needs to understand what numerical IP address it should contact to show up the content. The domain name server is a server responsible for keeping the file that contains information about the domain name(s) and corresponding IP addresses (zone file) as well as for providing the above-mentioned information during DNS queries.

Domain name servers are a fundamental part of the Domain Name System. Nameserver is a server on the Internet specialized in handling queries regarding the location of the domain name’s various services. In easy words, name servers define your domain’s current DNS provider.

How DNS works?

DNS is a global system for translating IP addresses to human-readable domain names. When a user tries to access a web address like “”, their web browser or application performs a DNS Query against a DNS server, supplying the host-name. The DNS server takes the host-name and resolves it into a numeric IP address, which the web browser can connect to.
A component called a DNS Resolver is responsible for checking if the host-name is available in the local cache, and if not, contacts a series of DNS Name Servers, until eventually it receives the IP of the service the user is trying to reach and returns it to the browser or application. This usually takes less than a second.

How does DNS increase web performance?

To promote efficiency, servers can cache the answers they receive for a set amount of time. This allows them to respond more quickly the next time a request for the same lookup comes in. For example, if everyone in an office needs to access the same training video on a particular website on the same day, the local DNS server will ordinarily only have to resolve the name once, and then it can serve all the other requests out of its cache. The length of time the record is held, or the time to live, is configurable. Longer values decrease the load on servers, shorter values ensure the most accurate responses.

DNS can do much more:

Now that’s we’ve covered the major types of traditional DNS infrastructure, you should know that DNS can be more than just the “plumbing” of the Internet. Advanced DNS solutions can help do some amazing things, including:

  • Global server load balancing (GSLB): Fast routing of connections between globally distributed data centers.
  • Multi CDN: routing users to the CDN that will provide the best experience
  • Geographical routing: identifying the physical location of each user and ensuring they are routed to the nearest possible resource
  • Datacenter and cloud migration: moving traffic in a controlled manner from on-premise resources to cloud resources
  • Internet traffic management: reducing network congestion and ensuring traffic flows to the appropriate resource in an optimal manner

These capabilities are made possible by next-generation DNS servers that can intelligently route and filter traffic.

DNS security

DNS does have a few vulnerabilities that have been discovered over time. DNS cache poisoning is one such vulnerability. In DNS cache poisoning, data is distributed to caching resolvers, posing as an authoritative origin server. The data can then present false information and can affect the time to live. Actual application requests can also be redirected to a malicious host network.


This article explained what a Domain Name System is, how it works, what DNS can do more, how DNS increases web performance and DNS security. It covered the essential DNS functions and what needs to happen before you can connect to an online server using its domain name.