What is a DNS?
In order to understand domain names, it is crucial to understand what is a DNS. The domain name system, or DNS, is a database for all websites. Consider it as the phonebook of the internet, through which users can find the address of the website they want to visit.
Overview of the DNS and its function in translating domain names into IP addresses
In reality, the internet works through IP addresses. These IP addresses are numerical numbers in a specific format, like 192.09.2.1. In fact, each device connected to the internet has its own IP address, which is difficult for humans to remember. At the same time, a website can also have one or more IP addresses, depending on whether it’s hosted on a public or private server.
Nonetheless, IP addresses are translated into domain names. The DNS servers read these IP addresses and translate them into domain names for humans to understand and remember. The computers and devices then communicate with each other and fulfill the users’ requests by communicating with each other using these IP addresses.
How does DNS work?
The DNS works in a series of steps that are performed in seconds. The task of the DNS servers is to read the user query and work on locating the website.
It is easy to understand the whole process if you know about the hierarchy of DNS servers.
· Step 1: User request
DNS servers start working as soon as they get a user query or request. This user query is the name of the website the user is looking forward to accessing. As the user enters the website address, e.g., www.abc.com, the DNS lookup starts working.
· Step 2: Checking the local DNS cache
After the query is entered, the user’s device first checks the local DNS cache for the record of the IP address. If the user has previously visited the site, the DNS work ends here. However, if the IP address isn’t found in the local DNS cache, the search continues.
· Step 3: Checking the local DNS resolver
The local DNS resolver is the server that receives the user’s search query next. To find the desired IP address associated with the domain name entered, it starts a recursive query process. It tracks down the local DNS cache records for the IP address and returns with a resolution. However, the request is transferred to the next server if it doesn’t find the record for the user’s query.
· Step 4: Checking the root DNS server
If the information isn’t found in the DNS resolver cache, the server requests the root DNS server. It’s a global DNS server that contains the records of all holding server’s top-level domains.
The job of the root DNS server is to send the IP addresses of TDL DNS servers to the DNS resolver as requested by the user. The resolver then contacts the TDL DNS servers.
In return, TDS DNS servers respond to the DNS resolver with the IP addresses of the authoritative DNS servers. The authoritative DNS servers are responsible for housing second-level domain names. The resolver then contacts the authoritative DNS servers with the request. If the user’s query is for the second-level domain, the authoritative DNS server fulfills the request and sends the required IP address.
· Step 5: Update the IP address in the DNS resolve cache.
The DNS resolver now has the required IP addresses updated in its cache. This helps in quickly resolving future requests related to the same IP address.
The DNS resolver also must respond to the user with the IP address.
The significance of DNS in internet navigation and communication
DNS plays an important role in internet navigation and communication. Some of its functions include:
- Helps humans access the internet in a language understandable by them. It’s responsible for translating the numerical value of IP addresses into domain names.
- Lets humans access the internet and websites across the globe, irrespective of geographical boundaries.
- Eliminates redundancy in data and balancing the load across multiple servers.
- Through DNSSEC (Domain Name System Security Extensions), it ensures that the security and authentication of information is passed from one DNS server to another.
What is a DNS, explained in a nutshell: DNS plays an important role in making the internet accessible to us. It helps translate IP addresses to domain names and is important to internet navigation and communication.