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Working Mechanism of DNS

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The internet has a wealth of information and interlinked sites, which feels almost magical. But beneath the surface exists a tough yet refined system popularly known as Domain Name System (DNS). 

DNS is the internet's invisible phonebook which silently translates user-friendly domain names such as google.com into the numerical IP addresses that computers need to communicate. Without DNS, navigating the broad internet looks like finding a particular house in a huge city without a street address, which is daunting.

Understand DNS Working

1. Initiating the Process

It all begins with you, as you are the user, typing a website address like "https://nordvpn.com/blog/what-is-google-dns/" into your browser. This easy action forms a chain reaction within your device, starting the quest to find the corresponding IP address.

2. Inspecting Local Cache

Before launching out into the broader web, your device asks for its local DNS cache. This cache is a small address book with the latest looked-up domain names and IP addresses. If "https://nordvpn.com/blog/what-is-google-dns/" is already in the cache, your device collects the IP address quickly, saving you precious time. However, this caching mechanism mainly enhances the browsing speed of often visited websites.

3. Using the Recursive Resolver

If the local cache looks empty, your device calls upon a DNS recursive resolver. This resolver has the role of your middlemen, taking the domain name and starting the hunt for the IP address on the wider internet. However, this resolver is like a skilled detective who has been given the task of finding the information you need.

4. Connecting to Root Nameservers

The recursive resolver's initial stop is the root nameservers. These are like a central directory in a broad library. However, the root nameservers do not have the IP address for every other website, yet they do have important information. The location of the servers responsible for particular Top-level domains (TLDs) such as ".com" ".net" ".org".

5. Track the TLD path

Depending on the domain name, such as "https://nordvpn.com/blog/what-is-google-dns/", the root server commands the recursive resolver to the TLD nameserver responsible e.g. ".com" nameserver. This TLD server has the information for all websites with the ".com" extension.

6. Find the Authoritative Nameserver

The TLD server doesn't have the particular IP address for "https://nordvpn.com/blog/what-is-google-dns/" either. Yet, it knows the address of the authoritative nameserver for "google.com". This authoritative nameserver, mainly operated by the owner of the domain, in this case, Google, is the main source of truth for all subdomains under "google.com", including "www".

7. Obtain the IP Address

The recursive resolver ultimately reaches the authoritative nameserver, which has the coveted IP address for "https://nordvpn.com/blog/what-is-google-dns/".

8. Deliver the Answer

The recursive resolver gets the IP address from the authoritative nameserver and sends it back to your device.

9. Cache the Result

Once your device gets the IP address, it mainly stores it in the local DNS cache for future reference. This sort of caching mechanism fastens up further visits to a similar website.

10. Connect to the Website

In the end, with the IP address with you, your device can set a connection with the web server hosting "https://nordvpn.com/blog/what-is-google-dns/". This lets your web browser fetch the website's content and show it to you.

The Power of a Distributed Network

It's vital to know that the DNS system is a distributed network, which means it's not reliant on a single central server. This distributed structure provides a plethora of perks:

  • Reliability: When one server goes down, others come to protect internet outages.
  • Scalability: The distributed nature permits the system to manage the ever-growing number of websites and users on the web. As the internet is growing, DNS can easily adapt and continue to function seamlessly and efficiently.
  • Security: A single point of failure turns less likely, making the system more resistant to attacks. Distributing the responsibility around multiple servers bolsters the over-security of DNS.

DNS Record Types and Security

While the main function of DNS spins around translating domain names to IP addresses, it goes deeper to operate multiple features through several record types:

  • A Records (Address Records): The workhorses of DNS, records map domain names directly to IP addresses. The record for "https://nordvpn.com/blog/what-is-google-dns/" would be marked to the numerical IP address of the web server hosting the content.
  • MX Records (Mail Exchange Records): All these records have a major role in email delivery. They mention the mail server responsible for receiving emails for a specific domain. When you send an email to an address such as [username]@mailto:[username]@[example.com], the MX record for "example.com" directs your email to the right server for processing.
  • CNAME Records (Canonical Name Records): CNAME records are aliases in the domain name space. They permit one domain name to point to another domain name. For example, a website might employ a CNAME record to direct traffic from a subdomain to the main domain.
  • NS Records (Nameserver Records): These records delegate authority to subdomains. Operating all the records on a single server can be tough for a big website with a variety of subdomains. ND records permit the owner to designate particular nameservers for subdomains, dividing the responsibility and enhancing efficiency.

Conclusion

By going deeper into the world of DNS, you get an appreciation for the behind-the-scenes wonder that supports your internet browsing. The next time you navigate to your favourite website, just keep in mind that this silent DNS work is happening and guaranteeing you a seamless and efficient web experience. 

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