What is DNS resolution and Why is it important?

In the vast landscape of the internet, where countless websites, servers, and services are interconnected, the Domain Name System (DNS) plays a crucial role in ensuring seamless communication. DNS resolution, a fundamental aspect of this system, might seem like technical jargon to many, but it is an essential function that keeps the internet accessible and user-friendly. In this article, we will explore what it is, how it works, and why it is of paramount importance in the digital age.

Understanding DNS Resolution

DNS resolution is the process by which a human-readable domain name is translated into the corresponding numerical IP address. Computers and network devices rely on IP addresses to locate and communicate with one another. However, for users, remembering complex IP addresses for every website they visit is impractical and challenging. This is where the DNS ( Domain Name System) comes into play.

When you type a URL into your web browser or click on a link, your device initiates a DNS resolution process to find the IP address associated with that domain name. This is accomplished through a series of steps involving DNS servers.

The DNS Resolution Process

Let’s break down this complicated process into several easy steps:

  1. Local DNS Cache: The process often begins with your device’s local DNS cache. If you have visited a website recently, your device may already have the corresponding IP address stored in its cache, saving time and reducing the load on DNS servers.
  2. Recursive DNS Server: If the IP address is not found in the local cache or if you are visiting a new website, your device sends a request to a recursive DNS server provided by your internet service provider (ISP). This server is responsible for handling the entire resolution process.
  3. Root DNS Servers: The recursive DNS server, if it doesn’t have the IP address in its cache, contacts the root DNS servers. These servers are the highest level in the DNS hierarchy and contain information about the authoritative DNS servers for top-level domains like .com, .org, and .net.
  4. TLD DNS Servers: The root DNS servers direct the recursive DNS server to the top-level domain (TLD) DNS server associated with the domain you are trying to access. For example, if you are visiting www.example.com, the TLD DNS server for .com is queried.
  5. Authoritative DNS Servers: The TLD DNS server, in turn, points to the authoritative DNS servers for the specific domain, which finally provides the IP address associated with the requested domain name.
  6. Return IP Address: Once the authoritative DNS servers respond with the IP address, the recursive DNS server caches this information and returns it to your device. Subsequently, your device stores the IP address in its local cache for future use.

Why Is it Important?

  • User-Friendly Experience: The process makes the internet user-friendly. It allows users to access websites, services, and resources by simply typing in easy-to-remember domain names instead of complex IP addresses.
  • Load Distribution: DNS resolution enables load distribution across multiple servers through techniques like round-robin DNS. This ensures that no single server is overwhelmed with traffic, contributing to better website performance and reliability.
  • Fault Tolerance: If one server or data centre becomes unavailable, DNS can redirect traffic to alternative IP addresses, minimizing downtime.
  • Geographic Redirection: DNS resolution can be used for geographic redirection, ensuring that users are directed to the nearest server or data centre for faster access and improved performance.

Conclusion

DNS resolution might be a behind-the-scenes process, but it is undeniably crucial for the functionality and accessibility of the internet. It simplifies how we access websites, enhances performance, and ensures that the internet remains a reliable and dynamic global network. So, the next time you type a URL into your browser, remember that DNS resolution is at work, translating your friendly web address into the numerical language of the internet.

Recursive DNS server – Main characteristics

Many people still ignore the importance of the Domain Name System (DNS) in our daily lives. The Internet gets the complete spotlight, but it totally relies on the DNS and its different components, the recursive DNS server, for instance. Let’s know the main characteristics of this important DNS component.

Recursive DNS server – Main characteristics

A recursive DNS server has an important job. It is in charge of searching the necessary data to respond to clients’ DNS requests.

When a user (potential client) requests a domain name through her or his browser, a recursive DNS server will look for the associated IP address of that domain. Without this information, the domain can not be loaded for the user. The recursive DNS server won’t stop its search due to one of its main characteristics, “recursion”. In the computing science field, recursion means a process or solution that repeats itself the necessary number of times to reach a specific goal. So the recursive server will look for the IP address until it finds it.

Once the DNS recursive server obtains the IP address, it will deliver it to the user’s browser. Then, and only then, the domain can be loaded by the user.

Another characteristic of a DNS Recursive server is that it has two ways to execute its job.

1. It can look for the DNS information needed to respond to the DNS requests within its cache. There is a chance for information to be kept available there. It will depend on the time-to-live (TTL) value previously set on the DNS record. If this TTL has not expired, the recursive will get the information and respond to the user very fast.

This is possible because the recursive DNS server’s cache can keep information for a specific period of time, not permanently. How long? The defined time on the TTL of DNS records (decided by administrators).

2. If the DNS record has never been inside the cache or the TTL has already expired, the DNS recursive server won’t find the necessary IP address in its cache. Then, the recursive will use a “B” plan. That means it will ask other servers for information. Its search must lead it to the exact, authoritative server that has the DNS information. It takes longer than checking in the cache, but it is an effective way to obtain DNS information.

When we say “longer”, we talk in milliseconds. It is a fast process.

To summarize, DNS recursive servers are essential for the DNS resolution process. Without them, DNS requests can not be answered. Therefore users can not load domains.

There are plenty of Recursive servers working 24/7, worldwide. Every user requesting a domain is a call to a recursive server to start a search.

DNS recursive servers search that is their duty, search for DNS information. They can keep DNS information but only temporarily.

Conclusion

Recursive DNS servers are essential for users to reach your online business! Walking through their main characteristics, you can better understand their value.