DNS (domain name system) is a decentralised hierarchical naming system for computers, services, and other resources connected to the Internet or a private network. The DNS converts domain and host names on the Internet to IP addresses and vice versa. Domain names are easy to remember because they are alphabetical.
IP addresses, on the other hand, are the foundation of the Internet.
As a result, every time you use a domain name, a DNS provider must translate the name into an IP address. DNS is used to swiftly supply the information needed to connect users to remote hosts during web browsing and most other internet activities.
In a hierarchy of authority, DNS mapping is disseminated over the internet.
The Domain Name System, which has been in use since 1985 and provides a worldwide, distributed directory service, is a fundamental component of Internet functionality. The domain name system functions similarly to a phone book on the Internet. You can look for a person’s phone number in a phone book if you know their name but not their phone number.
The Internet’s domain name system provides the same service. The DNS also describes the database server’s technological capability, which is at its core. As part of the Internet Protocol Suite, it defines the domain name system protocol, which is a complete specification of the data structures and data transfer exchanges used in the DNS.
How does DNS Works
When you type a URL into your browser, your DNS server utilises its resources to convert the name to an IP address for the correct Web server. This is analogous like dialling a phone number to reach the person you want to contact.
You do not, however, need to keep your own IP address book thanks to DNS. You just connect to a domain name server, also known as a DNS server or a name server, which maintains a huge database that maps domain names to IP addresses. Visit the Wikipedia DNS Page for more information.
Types of DNS Servers
The most prevalent DNS server types for resolving hostnames to IP addresses are shown below.
Primary Master Server
The master copy of the domain data is kept on the primary master server, and it is loaded onto the disc when it starts up. This is the primary server, which is used when relevant data is required; modifications to the database can be performed in the zone data on this server. In the event that the primary master server becomes overburdened, data is shared on the secondary server, which is given power by the primary server.
A secondary server is a sort of server that complements the primary server and performs a range of functions. It has the same features and capabilities as the primary server and serves as a backup or replacement in the event that the primary server is unavailable, busy, or overburdened. A slave server is another name for a secondary server.
Zone transfer Server
Zone transfer is the process of copying zone file information from the master server to the secondary server in order to replicate a zone file to another name server. When a domain’s names and IP address mappings change, zone transfers occur.
DNS Root Server
The root server is the initial step in the process of converting a hostname to an IP address. The DNS Root Server takes the user’s query’s Top Level Domain (TLD), such as www.example.com, and gives information for the.com TLD Name Server. As a result, that server will give information for names in the.com DNS zone, such as “example.com.”
The Internet Systems Consortium, Verisign, ICANN, the University of Maryland, and the United States Army Research Lab maintain 13 root servers around the world, designated by the letters A through M.
Caching-only Name Server
A DNS name server that can resolve name lookup requests but doesn’t have its own DNS database or zone file of resource records. Name servers that just cache data do not have their own DNS databases.
Instead, they make repetitive queries to other name servers to resolve name lookup requests from resolvers. The caching-only name server caches the results to these queries after they are received, in case another resolver submits the same request within a short period of time.
A name server that just caches data is not authoritative for any DNS domain.
It has the ability to look up names both inside and outside of its own zone.