In this online world, computers are usually represented as numbers, as that is the only way computers and other devices interact and identify each other over a network connection. However, the DNS, or domain name system, is essential for today’s advanced networking system. DNS usually translates between a human-readable domain name and an IP (internet protocol) address, as these connect the devices and help them communicate with each other.
DNS existed even before the WWW (World Wide Web), and it provided the facility online for all communication happening daily on the internet. It was developed in the 1980s, so it had several security issues in network protocols, which led to various weak points and attacks online.
However, we are unaware of the functionality of DNS based on our daily internet usage for various purposes. Yet, it is essential to understand the DNS and how it functions behind the scenes.
As a result, in this article, you will learn about the critical details of DNS and how it works.
What is DNS?
No matter what device you use, whether a computer, smartphone, or laptop, to access certain websites and pages on the internet, while using the internet on all these devices, they utilise the numerical digits as their permanent address to locate and interact with each other by utilising numbers. These numerical digits are technically the IP addresses.
However, it could not be enjoyable to remember and enter those numbers to access that website every time you want to visit a website. Here comes the central role of DNS, as you can enter a domain name like example.com and still access a particular website without having to remember the IP address of each site. You must ensure that the name entered to open the site is the DNS or domain name of the website you wish to access.
Many DNS services universally interpret human-readable names like www.example.com and convert these names into IP addresses. Because our devices use IP addresses to connect.
The Internet’s DNS system manages and maps between domain names and IP addresses.
Simply put, DNS servers interpret the request for domain names into IP addresses. It also controls which server an end client will arrive at after entering the specific domain name into their web browsers. These requests from the browser to the server are usually queried.
Types of DNS Servers
DNS is a distributed system in which all servers globally interact and work together and maintain the delivery of DNS records. There are four types of DNS servers available;
1. DNS Recursor
A DNS precursor is also known as a recursive resolver. It is a DNS precursor that receives inquiries from DNS clients, and it reacts on the off chance that a hit is accessible in the cache or contacts a nameserver and builds up the chain. Internet service providers usually run the precursors, yet it’s pretty easy to change the DNS settings of your device or computer to highlight one more source for execution, security, or privacy concerns.
2. DNS Root server
As clear from the name, the DNS Root server is the base that helps to grow the entire DNS infrastructure. For the top-level domains like .com and .net, Root servers act as the authentication name server. However, in case there is some issue, the root servers themselves are alluded to by hostnames inside those same TLDs.
On the off chance that a DNS client cannot find precisely which nameserver to go to for “.net,” how could it help to solve an entire domain like “a.root-servers.net”?
Hence, the 12 root server IP address list is within the DNS clients, and lower-level servers are “bootstrapped.” Thus, these locations don’t usually change, and just one of them should be reachable to determine the others.
3. TLD Name server
TLD Name Servers, like root servers, are important server points because they are likely to know where to go for answers about any domain within a given TLD.
When a user searches for a specific domain name, such as “example.com,” a TLD server for the “.com” will first response, and it will then redirect the user to the requested name server with the records for the “various.” part of the domain name.
4. Authoritative Name Server
Authoritative servers are the final stop point for DNS queries. For redundancy, this server consists of top-end authority power for a given domain. Although it is not essential that all the DNS queries make it to the authoritative server, there might be cache outcomes that are closest to the final request.
Various associations usually use the DNS internally. The only difference is that the DNS queries and records are sent through the corporate network rather than the internet.Thus, it is also known as the “private” or “local” DNS compared to the public DNS service.
How do DNS functions?
Being an integral part of the internet, DNS is critical to understanding how it functions. Consider DNS a telephone directory, yet instead of keeping people’s name records with their addresses, it usually maps computer names to IP addresses. Thus, these record plans are also known as “DNS records.” DNS clients with their connected devices link with the DNS servers to access these records. However, distinctive record types are utilised for various purposes. Internet browsers depend on “A” type records, while the mail server is focused on the “MX” record.
It is impossible to keep all the records in a single book, yet the internet has numerous computers. For this, the DNS is further divided into small record books or domains. Yet, domains could be significant, so these are categorized into small books known as “zones.” It is not possible to store all the record books on a single DNS server, as it is impractical.
DNS works in a categorized manner, with a considerable number of servers all over the planet working together. Your computer asks for the DNS server on the local router whenever it needs to send the DNS query. The local router will make an “upstream” inquiry to one more DNS server, provided by an ISP. The queries for a domain can go “upstream” until they arrive at the domain’s authority, or “authoritative server.” In reality, the cache is used to store the results at lower levels, preventing the need to repeat the same process from the beginning.
The server name and IP addresses are maintained by the administrator for the domains, and it also sets up an authoritative name server. However, whenever a DNS administrator requests that a server name or IP address be changed, removed, or added, the authoritative DNS server, also known as the “master DNS server,” is updated.On the other hand, there are “salve DNS” servers that store the copies of DNS records for their zones and domains.
DNS Queries
The DNS name server is able to return the non-recursive queries with the cache record data. Perhaps, optimizing the distance traveled and optimizing DNS process resolution helps. However, the DNS lookup only consists of three types of queries. So let’s have a look at all these queries;
- Recursive Query – In this type of query, a DNS client demands a DNS server or, more commonly a DNS recursive resolver that will react to the client with the mentioned resource record or with an error message if the resolver can’t track down the record.
- Iterative query – Currently, the DNS client will enable the DNS server to make a return request to get an accurate response in every possible way. However, if the queried DNS server doesn’t have an exact match for the inquiry name, in that case, it will return a reference to a DNS server authoritative for a lower level of the area namespace. The DNS client will then, at that point, inquire about the reference address. This interaction proceeds with different DNS servers down the question chain until an error or timeout happens.
- Non-recursive query – Under this query, the DNS resolver client inquires a DNS server for a record that it approaches as the same record exists in the cache or it is an accurate record to utilize. In general, to prevent extra bandwidth usage, the DNS server will cache DNS records, and it will also load upstream servers.
Conclusion
In summary, you now have a clear understanding of what a domain name server does on the internet, as well as how this service maps domain names to IP addresses. Understanding that DNS is more than just a static concept is important. The status of DNS is even more complex.
DNS is evolving day by day with the latest security features that also affect the cryptographic keys in the security system. No doubt, these certain measures and updates are essential to prevent any online threat from hackers from tapping into any DNS system that could compromise personal data. The new DNS over the HTTPS paradigm is the settled way to potential configurations and changes.