DNS stands for the Domain Name System. Domain Name System is the database that stores the internet’s domain names. Domain names are translated into the IP (Internet Protocol) addresses at DNS. All the internet services and search engines depend on the DNS to provide the needed information to people.
- Authoritarian hierarchy plays a major role in distributing DNS throughout the internet search engines.
- There are particular IP address ranges for governments, educational institutes, business organizations, etc.
- DNS figures out the names used by the people for the website on the internet and then locate the website’s name with the IP address that the computer assigns for the website.
- For example Type facebook.com in the web browser of the computer.
- The internal server of the internet will match the domain name similar to the name written.
The detailed structure of DNS
The DNS design has a specific set of rules and regulations. Internet Engineering Task Force is the special body that defines and operates the rules and regulations for internet protocol. The implementation of DNS must be according to the rules of the Internet Engineering Task Force.
- The URL of any website or webpage holds its domain name.
- There are multiple fragments of domain names which are usually called labels.
- The reading of the domain is done from right to left.
- The domain names are divided into sections as well as subdivisions.
Top-level domain names are
- Some domain names include the country names in it. Such as .ca – Canada and .us – United States
- The left side of the domain name is the subdomain. For example : www.Facebook .com. In the above example, Facebook is the subdomain under .com. Each subdomain can have a maximum of 127 labels. Each label may comprise 63 characters. The domain name cannot be fully numeric.
How DNS works
The URLs and domain names that the user feeds can’t be understood by the computer. The DNS converts the domain names and URLs into IP addresses. The user types the website’s name, converted into machine language by the domain name system. The user requires the IP address to search for the webpage.
- When a user types the web address in the search bar of a search engine, then a message is sent by the web browser to the internet network.
- That message is called a recursive DNS query. This query is generated to direct the network to initiate the search for the web address needed by the user.
- DNS query is further directed to a server called recursive DNS server. This server has webpages address, and the Internet service provider updates and manages the recursive DNS server.
- When the webpage needed by the user is available in the recursive DNS server, then it will show up on the result page.
- When the webpage needed by the user is not available in the recursive DNS server, then the query will further be sent to three other servers, such as
Top-level domain name servers
- Root name servers
- Authoritative name servers
- These three servers work together to retrieve the required webpage. If this server finds the relative webpage, then the DNS server forwards the IP address of the required webpage to the network to load. But if no webpage is found according to the name given by the user, then an error message is shown on the search engine as the final result.
- Caches are the search history for the web pages stored by the recursive server. Whenever the user uses the search engine for the same web page, it is directly shown up by the recursive DNS server without further query.
There are four types of Domain Name System servers
The DNS server stores the domain name and helps the network find it when the query is forwarded to them.
Top-Level Domain server: When the query is more specific and related to top-level domains, it goes to the top-level domain server. The top domain server includes top domains like .com, .edu, etc.
Recursive DNS server: This server gets the queries from the web browser itself. The queries can be searched by using the previously stored cache.
Authoritative name DNS server: The authoritative name DNS is the final destination for any search engine query. This server has full information about all the domain names and IP addresses, and these servers contain records of all the domains. Once the search is directed to the authoritative name DNS server, it looks into its records and passes on the information to the recursive DNS server to show it to the end-user.
Root name DNS server: When the query is not resolved in the recursive DNS server, it is sent to the root name DNS server. The root name contains the list of the servers available that could help with the query search.