What is DNS and how does it work?

The DNS (Domain Name System) is a system that allows computers to communicate with each other using domain names instead of numerical IP addresses. This makes it much easier for users to access websites and services on the Internet, rather than having to memorize long sequences of numbers.

How does DNS work?

When you type a domain name into your browser (e.g., www.vertexa.com.br), the browser sends a request to the DNS server to obtain the corresponding IP address for the domain name. This is known as name resolution.

The DNS server then checks its DNS records table to see if it has the IP address for the requested domain name. If it doesn’t, the DNS server forwards the request to another DNS server that may have the necessary information. This process continues until the correct DNS server is found and returns the correct IP address to the browser.

The IP address is then used by the browser to establish a connection with the website’s server. The web page is downloaded from the server and displayed in the user’s browser.

Types of DNS records

There are various types of DNS records that can be stored in a DNS server. Some of the most common ones include:

• A Record: This record associates a domain name with an IP address. It is used to resolve domain names into IP addresses.
• MX Record: This record is used to direct email traffic to a specific email server associated with a domain name.
• CNAME Record: This record is used to create aliases for existing domain names. For example, it is possible to create an alias “www” for the domain name “mywebsite.com.”
• TXT Record: This record is used to store arbitrary text information associated with a domain name.

Benefits of DNS

DNS offers several benefits for Internet users. Some of the key ones include:

• Ease of use: DNS makes it much easier for users to access websites and services on the Internet by using domain names instead of having to memorize numerical IP addresses.
• Scalability: DNS allows the Internet to grow in a scalable manner, without the need for constantly upgrading hardware and software to accommodate more devices.
• Redundancy: DNS enables the configuration of redundant servers to provide failover resilience in case of network issues.

Conclusion

DNS is one of the core systems that make the Internet possible. It allows users to access websites and services using easily memorable domain names instead of typing complex numerical IP addresses. Additionally, DNS provides scalability and redundancy, making the Internet more reliable and resilient to network failures.